# Harder, Better, Faster, Stronger: Optimising the Performance of Context-Based Password Cracking Dictionaries

## Full Text

This Markdown is an automated text extraction for search and reading tools. The [hosted PDF](OptimisingPasswordCrackingDictionaries.pdf) is the authoritative publication source.

Source PDF: [OptimisingPasswordCrackingDictionaries.pdf](OptimisingPasswordCrackingDictionaries.pdf)
Source SHA-256: `4ce076e11780e2fbe2be13ee62eaddcab3d7764a5e6bab5ad2ebcd6dc96c453e`
Generated with `pdftotext -nopgbrk`; formatting and reading order may differ from the PDF.

---

Forensic Science International: Digital Investigation 44 (2023) 301507

Contents lists available at ScienceDirect

Forensic Science International: Digital Investigation
journal homepage: www.elsevier.com/locate/fsidi

DFRWS 2023 EU - Selected papers of the Tenth Annual DFRWS Europe Conference

Harder, better, faster, stronger: Optimising the performance of
context-based password cracking dictionaries
Aikaterini Kanta a, *, Iwen Coisel b, Mark Scanlon a
a
b

Forensics and Security Research Group, School of Computer Science, University College Dublin, Ireland
Europol, Eisenhowerlaan 73, 2517 KK, The Hague, Netherlands

a r t i c l e i n f o

a b s t r a c t

Article history:

Passwords have been the prevailing method of authentication since their inception more than 50 years
ago, a trend which has no signs of slowing down in the foreseeable future. They are an integral part of the
security of digital persons, systems and critical data, and yet, they often remain the weakest entry point
to a digital system. A password itself is indeed an extension of its creator and therefore can be exploited
by malicious actors leveraging available contextual information about a target password creator. Recent
research has shown that bespoke password candidate lists, generated based on available contextual
information, can positively impact the password cracking processes. This paper introduces an innovative
methodology for composing a contextual wordlist and ranking the password candidates in order to
maximise the chance of early success. The aim of the proposed approach is to support digital forensic
investigators in their criminal investigation e especially when time is of the essence. This paper describes the implementation of this methodology and provides an overview of several experimental results demonstrating the advantages of this approach. These results demonstrate that by going through a
harder, more rigorous password candidate selection process, better dictionaries can be generated that, in
a faster timeframe, can crack stronger passwords.
© 2023 The Author(s). Published by Elsevier Ltd on behalf of DFRWS This is an open access article under
the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Keywords:
Dictionary
Contextual information
Password cracking
Wordlist

1. Introduction
For the last few decades, research on passwords, their architecture, and the ways to crack them has been a focal point for researchers. This is with good reason, since they have been the most
popular means of user authentication e and are set to continue to
be so into the foreseeable future (Kanta et al., 2020a). Attackers
refine and adapt their methods to account for the increasing diligence of companies and users who choose harder and stronger
passwords, often times computer generated and/or salted.1 By
taking into account the increasing usage of computer generated
passwords, the addition of salts, and the use of slower hashing
functions, password cracking is increasingly becoming more of an
uphill battle. This redoubles in the context of an attacker trying to
gain access into a single account/point of entry, especially for an

* Corresponding author.
E-mail addresses: aikaterini.kanta@ucdconnect.ie (A. Kanta), iwen.coisel@
europol.europa.eu (I. Coisel), mark.scanlon@ucd.ie (M. Scanlon).
1
A salt is a string that is combined with the password plaintext and subsequently
that combination is hashed, resulting in different values for the same password.

online system with a limited number of tries. In this case, simply
brute forcing is out of the question e more sophisticated password
cracking attacks need to be employed.
In the case of a law enforcement digital forensic investigation,
the investigator could be faced with the encrypted system of a
perpetrator, which can pose a significant hindrance to the investigation, or bring it to a halt entirely (Du et al., 2020). Suspects are not
always inclined to share their passwords, especially if there is
incriminating information in them. In many jurisdictions, law
enforcement cannot compel that information from them (Ryder
and Le-Khac, 2016). Furthermore, in a triage situation, where the
discovery and processing of evidence in a timely manner is crucial
to the outcome of the investigation, it becomes paramount to access suspect devices as quickly as possible. Therefore, generic approaches like a brute force attack, or an extensive dictionary search
would not be suitable because of time constraints and other
methods should be considered.
Research shows that the distribution of passwords of users is not
uniform (Wang et al., 2017) and users tend to gravitate towards
passwords that contain information that is personally connected to
them (Wang et al., 2016). Many approaches take this information

https://doi.org/10.1016/j.fsidi.2023.301507
2666-2817/© 2023 The Author(s). Published by Elsevier Ltd on behalf of DFRWS This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/
licenses/by-nc-nd/4.0/).

A. Kanta, I. Coisel and M. Scanlon

Forensic Science International: Digital Investigation 44 (2023) 301507

2. Related work

into account, using leaked lists of real-world passwords for password cracking and/or mangling rules2 to mimic user tendencies
(Kanta et al., 2020a). One such user-centric method would be to
focus on the individual whose password needs to be cracked, and
more specifically, the information available about them through
open source intelligence or other investigative means (Kanta et al.,
2020b). This will result in an attack that is tailored to the individual
target, which could return results when traditional methods fail.
In this case, it is essential for the investigator to have at their
disposal the necessary bespoke dictionary lists, those that focus and
contain password candidates that closely align with the suspect’s
interests and hobbies. To assemble such lists, natural language
processing can be used, to create a concentrated body of words that
align thematically with a starting seed word. The process of
creating custom dictionary lists was introduced by Kanta et al.
(2022).

The number of passwords users are required to remember
nowadays has been steadily increasing for decades (Kanta et al.,
2020a). This results in users being more inclined to seek easy
ways to facilitate recalling them from memory. It is widely accepted
that when users select their passwords, they follow certain patterns, using symbols and phrases familiar to them in an attempt to
produce a “memorable” password (Wash et al., 2016a). This means
that user-generated passwords are more susceptible to password
cracking compared to machine-generated ones with random distribution of characters. To this end, various techniques have been
developed to leverage that inherent weakness.
2.1. Password cracking techniques
For machine-generated, apparently randomly passwords, no
cracking strategy would have an advantage over an exhaustive,
brute-force search e where all combinations of a given alphabet,
including digits and special characters, up to a predetermined length
are tested. Exhaustive searches are guaranteed to work if maximum
password length or limits for attempts are not defined e the only
variable is time. But even with modern, state-of-the-art graphic card
aided brute-forcing, if slower hash functions are used, the time it
would take to perform is computationally infeasible, i.e., an
exhaustive search could potentially take millions of years. Therefore,
this approach is not efficient from both a computational and a timelimited point of view. To leverage the “weakness” of user generated
passwords, a vast array of password cracking techniques have been
developed. This varies from the more traditional, e.g., an off-the-shelf
dictionary based attack, to the more recently developed, e.g.,
Rainbow Tables (Oechslin and Boneh, 2003) or Markov-based
models (Narayanan and Shmatikov, 2005).
Rainbow tables are based on the idea of a time-memory tradeoff (TMTO), which focuses on pre-computing an almost exhaustive
predefined search space of passwords. The main advantage of this
approach is that these tables store a minimal amount of information, and thus, enable a fast lookup of a password if it exists in the
predefined search space. This approach needs less computer processing time but more storage than an exhaustive search, which
calculates the hash on every attempt. The use of salting, as a
method of protecting the password by changing its hash according
to the salt, has become a hindrance to rainbow tables. This is
because the same password salted with a different salt will almost
certainly produce a different hash e therefore resulting in an
infinite number of combinations. Only if the investigator knows
beforehand that the length of the password in question is small, can
a rainbow table be considered a reasonable possibility. Many efforts
have been made to improve this procedure, like focusing on precomputation using cryptanalytic TMTOs (Avoine et al., 2021).
Markov-based models are focused on reducing the search space
(Narayanan and Shmatikov, 2005), or are used to produce password
candidates in descending orders of likelihood (Dürmuth et al., 2015).
Another recently used approach to make use of probabilistic contextfree grammars e where Markov chains are used to calculate the
probability for each grammar (Weir et al., 2009). Neural networks are
also utilised for password cracking, offering the advantage that they do
not require user input (Pal et al., 2019; Melicher et al., 2016). PassGAN,
which uses a Generative Adversarial Network (GAN), is an example
neural network used to create password candidates that closely mimic
the distribution of real-world passwords (Hitaj et al., 2019).

1.1. Contribution of this work
In this paper, a methodology for optimising and ranking the
candidates of a custom-made dictionary list is presented. This work
aims to aid law enforcement investigators during criminal investigations by providing dictionary lists for password cracking
that are tailored to the suspect. These are subsequently ranked so
that more suitable password candidates are checked first, in a bid to
save time during an investigation. The methodology described in
this paper can become an important tool in an investigator’s toolkit,
by providing readily available, highly-customised contextual dictionaries on any topic e however niche. This approach is evaluated
as part of this paper with data leaks stemming from compromised
online communities focused on specific topics, as accessing a sufficient number of individual user’s information is not possible.
Nonetheless, the contextual approach proves itself valuable in
finding many passwords that were not recovered with the baseline
technique. These passwords are thematically close to the community itself, thus proving the role of context in password creation.
Furthermore, the optimised, ranked dictionary lists as presented in
this paper offer a significant increase compared to the models
introduced in the past, as will be outlined in greater detail in Section 5.
To summarise, the contribution of this work includes.
 A thorough presentation of the optimisation and ranking techniques that were used for curating the contextual dictionaries.
 An example scenario focusing on a digital forensic triage use
case is used in combination with the results presented to
highlight the potential impact and improvement of contextual
dictionaries over traditional password cracking methods.
 A detailed discussion section highlighting the uses, benefits and
limitations of leveraging context in password cracking.
The rest of the paper is organised as follows: Section 2 offers an
overview of the related work in the field. Section 3 provides the
methodology that was used to create the optimised and ranked
contextual dictionaries. Section 5 shows the result of putting this
methodology to use across four different data leaks and provides an
analysis of the results, and finally Sections 6 and 7 provide a
summary and commentary of the results and outlines several avenues for future work.

2
Mangling rules represent common behaviours and substitutions by users in
their passwords. For example, adding numerical sequences at the end of the
password or replacing alphabet letters by similarly looking numbers or symbols
(i.e., ‘1’ for ‘i’ or ‘@’ for ‘a’).

2.2. Password selection and strength
Passwords have been used for decades to protect sensitive
2

A. Kanta, I. Coisel and M. Scanlon

Forensic Science International: Digital Investigation 44 (2023) 301507

information from adversaries. But in many cases, they can represent the weakest point of entry to a system and therefore be the
target. This is because the password is often connected to its
creator, which presents an inherent weakness that criminals look to
profit from. Users tend to use their own personal, identifiable information when they create passwords as a way to more easily
memorise them (Li et al., 2017).
Furthermore, and because users are required to memorise an
abundance of passwords across the different services and devices
they use, they tend to reuse the same passwords, verbatim or
slightly modified versions of a “root” password (Florencio and
Herley, 2007; Bonneau et al., 2012a). This practice, of course, creates a risk that even strong passwords can be rendered vulnerable if
a password that has been reused has been somehow leaked, either
through a phishing attack or as part of a data breach (Wash et al.,
2016b).
Users often tend to overestimate the security of the passwords
they create (Ur et al., 2016). Common practices that have been
observed in passwords from data breaches show that users, when
asked by a password policy to have uppercase characters in their
password, they will most likely capitalise the first letter (Kanta
et al., 2021a). Similarly, if it is required to include numbers in the
password, usually they are found at the end of the passwords and
are often sequences, or they represent dates (Kanta et al., 2021a).
Even in cases where they are required to use passphrases as a
means of authentication, that choice was far from random, as users
tended to prefer simple noun bigrams (Bonneau et al., 2012b).
Therefore, adhering to a password policy, might provide users a
false sense of security (Ur et al., 2015).
Password strength meters are often used by web services to
guide users and help them develop safer password creation habits.
One of the most well known policies was introduced in 2013 by the
National Institute of Standards and Technology (NIST)3 and it requires passwords to be at least 8 character long, with uppercase,
lowercase, digits and special characters included (Grassi et al.,
2017). But even when these policies are enforced, users still try to
bypass them in favour of memorability. For example, if a web service requires a password to be changed every six months, users
might keep the same password by adding a 1 at the end (Kanta
et al., 2021a).
The password strength meters that are now in use have also
evolved to anticipate this behaviour by users and often detect and
disallow passwords that contain the same basic structure as previously used (Shay et al., 2015). There are many strength meters
available and in use by various web services, some based on Markov
Models (Castelluccia et al., 2012), Natural Language Processing (Guo
and Zhang, 2018) and Deep Learning (Pasquini et al., 2020). It has
also been shown, that the results found by the various password
strength meters when evaluating the same passwords have been
 de Carnavalet and Mannan, 2014).
widely inconsistent (de Carne

Table 1
Size of datasets.
Size

AxeMusic
JeepForum
Wattpad
MangaTraders

252,752
239.347
23,531,304
618,237

specific scenarios aimed at minimising the duration of the process.
One viable alternative approach is to leverage the role of context in
a user’s password selection. In order to prove its viability, an
experimental methodology is presented in this section, focusing on
the creation, ranking and optimisation of bespoke dictionaries for
specific topics.
Ideally, the evaluation of the proposed methodology would
include testing the contextual dictionaries against specific targets
during the course of an investigation. For example, if a digital
investigator wanted to access the encrypted device of a suspect
who was known to be a fan of rock music, football and tennis, a
dictionary could be created using these topics as seed words. Unfortunately, for data protection and ethical purposes, access to this
privileged information is not possible. Therefore, the approach for
evaluation is focused on communities’ passwords as opposed to
that of individuals. For this purpose, four different data leaks have
been selected from four communities, about music, cars, fanfiction
and manga. These datasets and their sizes can be found in Table 1
and contain the passwords from the leaks without any other
identifiable information, i.e., the datasets used do no contain
usernames, e-mail addresses, phone numbers, etc. Approval for use
of these datasets has been given by the Office of Research Ethics of
University College Dublin.
As a baseline to compare this approach against existing ones, a
dictionary named Ignis-10M4 has been selected. Ignis contains 10
million passwords from a variety of data leaks and was assembled
in 2020. The reason Ignis has been selected instead of the popular
RockYou dictionary list is that although the passwords of RockYou
have been leaked as plaintext and therefore represent a more accurate account of real-life passwords, RockYou was leaked in 2009.
Password policies have evolved significantly since then, i.e., password policies have become stricter regarding their requirements e
with a larger minimum length and a mix of upper and lowercase
characters, numbers, and symbols often all being required.
Furthermore, according to the creator of Ignis, when looking at the
Top 1000 passwords in Ignis-10M and RockYou, 411 passwords of
Ignis were not in RockYou’s Top 1000. This is likely due to RockYou
only containing passwords created up to 2009. For example,
“Minecraft”, which is a Top 1000 password, does not exist in
RockYou due to the game being released in 2011. Using Ignis-10M as
the dataset to compare this approach against provides the most upto-date baseline.

3. Methodology for ranking and optimising contextual
dictionaries

3.2. Contextual dictionary generation

3.1. Selection of evaluation and control datasets

The method used for creating the contextual dictionaries as part
of this work is described in Kanta et al. (2022). This method starts
with selecting a seed word that is thematically close to the community from which the leaked dataset stems is picked. This seed
word is then used with DBPedia,5 a crowd-sourced knowledge
graph database version of Wikipedia, in order to visit the corresponding DBPedia entry and gather the titles of all the other articles

Access to the content of the encrypted devices of a suspect can
be crucial for the outcome of the investigation (Sayakkara et al.,
2018). The timeliness of accessing potentially case-progressing information can be paramount in certain scenarios, e.g., kidnapping
cases or an imminent terrorist attack investigation. Investigators
might seek alternative methods of password cracking in these

4
3

Dataset

5

https://pages.nist.gov/800-63-3/sp800-63b.html.
3

https://github.com/ignis-sec/Pwdb-Public.
https://www.dbpedia.org/.

A. Kanta, I. Coisel and M. Scanlon

Forensic Science International: Digital Investigation 44 (2023) 301507

vector space, i.e., a score of 1 would mean they are identical.
With this similarity score in hand, the words in the wordlist are
ranked accordingly with the seed word, from the highest similarity
score to the lowest. This means that not only will the words that are
higher on the list be checked first, but also more permutations of
them with mangling rules will be checked during the attack. At this
stage a threshold can be set for the similarity score, for example
words below a certain threshold could be considered as irrelevant
to the seed word and therefore disregarded.

Table 2
The DBPedia dictionaries.
Seed Word

Size

Corresponding Dataset

Music
Car
Fanfiction
Manga

1,001,173
853,825
641,007
6,348,947

AxeMusic
JeepForum
Wattpad
MangaTraders

it links to. As part of this work, this is referred to as “Layer 1”. The
reason for this is that in any given Wikipedia article, the important
links are usually also keywords relating to the given article. After all
these entries are collected, they are in turn visited and the new
articles are also processed and added to the total, thus creating
Layer 2. This process can go on until the required depth of search is
reached. The end product of this process is then sanitised and can
be used as the input wordlist in a dictionary attack.
Of course, the deeper the traversal down the DBPedia tree, the
less thematically close the new keywords are and the size of the list
increases exponentially. It is therefore important to be able to reach
a satisfying length for the wordlist, while also making sure the
terms are still thematically relevant to the seed word. For this
reason, both the parameters of size of the wordlist and thematical
distance to the seed word were explored.

3.5. Words vs. entities
As described above, the source of the entries in the wordlist are
Wikipedia articles, linked to the seed word, either directly or
through other articles. During the sanitation process, many of these
are disregarded due to their format, e.g., an image name is a link but
not very useful for a dictionary attack. From the remaining entries,
some are single words and some are phrases/entities. Entities have
embeddings in Wikipedia2Vec, and therefore a similarity score
can be computed for them as well e resulting in a more complete
ranking of all the wordlist entries. However, some entries are not in
the training model and therefore a similarity score cannot be
computed. Two avenues were explored to deal with this issue. One
was to compute the average similarity score for each word in the
entity, and the other was to assign the score of the word that was
closest to the seed word to the entire phrase, i.e., the maximum. For
example, if the seed word was “Shopping”, the phrase “Window
Shopping” would be assigned a score of 1.
However, as can be seen from the above example, while “window shopping” is very relevant to “shopping”, it does not seem like
a very likely password. Therefore, two ranked versions of the
wordlists were produced. In the first version, phrases were also
contained in the list, and they were ranked as described above. In
the second version, the phrases were split into single words and
then ranked (duplicates and stopwords were removed).

3.3. Size of the wordlist
It has been observed that the size of the wordlist in a dictionary
attack plays an important role in the percentage of found passwords (Kanta et al., 2022; Bosnjak et al., 2018). In fact, the larger the
dictionary list, given an infinite amount of time and permutations,
the more passwords will be cracked. This is why given infinite time,
a brute force attack is guaranteed to work. In this case, the depth of
traversal in DBPedia for all four seed words was chosen to be either
Layer 3 or 4. More specifically, Music, Car and Fanfiction, being
larger Wikipedia articles with more links, were chosen to be Layer
3, while Manga was chosen to be Layer 4. The reason for this was
that Layer 3 for Manga contained only ~180,000 candidates and
considerably under-performed compared to the equivalent of Layer
4. The sizes of the produced dictionaries can be found in Table 2.

3.6. Quality of the dictionary list
Evaluating a dictionary list is a complex topic and there are many
parameters to take into consideration (Kanta et al., 2021b). For
example, a larger dictionary list can achieve a higher percentage of
found passwords, but in twice as much time as a smaller list. Alternatively, two lists can have the same size, a similar run-time, and
achieve similar success rates, but one of them can find passwords of
higher difficulty. Therefore, this trade-off should be considered on a
case-by-case scenario. For an offline attack where the percentage of
success is important, a bigger, more thorough dictionary list might be
chosen and paired up with an extensive set of rules for permutations.
If time is of the essence, a smaller dictionary list might be more
beneficial. If the target is a single password, a combination of bruteforcing the smaller passwords alongside a contextual dictionary list
focusing on harder passwords might be an optimal strategy. The
dictionary list, or combination thereof, should be decided depending
on the parameters of the specific case.

3.4. Thematical distance
Another important aspect of the creation of bespoke wordlists
on certain topics, was making sure that the words were indeed
thematically close to the seed word. In order to ensure this, the
natural language model Wikipedia2Vec was used (Yamada et al.,
2020). Wikipedia2Vec is a NLP model based on Word2Vec
(Mikolov et al., 2013). Word2Vec can compute vector representations (referred to as embeddings) of words relying mostly on the
surrounding context present in the training dataset. It relies on the
Harris’ “Distributional Hypothesis” stating that words that occur in
the same contexts tend to have similar meanings. The word embeddings can subsequently be used to estimate the similarity of the
context in which they have appear in the training dataset and
therefore similarity in their meaning. Wikipedia2Vec provides
embeddings not only for words, but also for entities, i.e., entries
that have corresponding articles on Wikipedia. For this purpose, a
pretrained embeddings model of Wikipedia in English was used.6
Using Wikipedia2Vec, the similarity of each word of the
bespoke wordlists can be evaluated. This evaluation returns a
similarity score according to how close the embeddings are in

6

4. Experimental scenario
For the purpose of this paper, a digital investigation triage scenario is selected, where the investigator needs to access the data on
an encrypted device as soon as possible. There are many dictionary
lists in existence, given a more relaxed time frame and an abundance of resources, that can perform very well (especially when
looking at sheer numbers of cracked passwords). However, it is the
performance against one (possibly harder) password where the
speed of cracking is of the essence. Therefore, a limited execution

https://wikipedia2vec.github.io/wikipedia2vec/pretrained/.
4

A. Kanta, I. Coisel and M. Scanlon

Forensic Science International: Digital Investigation 44 (2023) 301507

dictionary for the JeepForum dataset.
Table 3 shows the overall number of passwords found by each
dictionary and for each data leak. It can be observed that Ignis-10M
and the Music_R (representing the ranked version of the dictionary
created with “music” as the seed word) have very similar performances, which is a positive outcome considering the size and variety of real-world passwords in Ignis-10M. The same holds true for
Ignis-10M and Car_R. It is worthy to note that size wise, the dictionaries produced by the seed words “car” and “music” were the
two smallest, as can be seen in Table 1. It can also be observed that
in all four categories, the ranked versions have outperformed the
unranked ones, most strikingly in the Wattpad leak e where
ranking resulted in an increase of 27.44% in performance.
Table 3 also shows the passwords that have been found exclusively by the ranked and unranked dictionaries for each topic. This
is especially valuable if a combination attack is considered, i.e.,
where Ignis-10M is first used to target the weaker, more common
passwords and subsequently the targeted contextual dictionary is
employed (or indeed, both ran in parallel across different workstations). In this case, the improvement offered by the contextual
dictionaries over Ignis-10M alone is significant across the board e
with once again, the ranked dictionaries outperforming the unranked ones. This is especially true in the case of Wattpad, there are
more than a quarter of a million of new passwords, exclusively
found by Fanfiction_R that were not found by Ignis-10M. This
represents an increase of 6.55%.
The number of passwords found exclusively by the contextual
dictionaries leads to a new and interesting question. Which password candidates in the dictionary list performed better, i.e., which
found the most passwords in their respective data leaks? Table 4
shows the top 20 password candidates that found the most passwords by the ranked dictionaries across all four topics. As can be
seen, the top password candidate for Music_R is the word “music”
and the rest of the top 5 are also words relating to music. In fact, 14
out of the top 20 best performing password candidates for AxeMusic are music related e something that reinforces the theory
that users pick passwords according to their interests, and also the
type of website the password is aimed for. Similar results can be
observed for “car” and “manga”, with 13 out of 20 password candidates in Car_R being related to cars (this is excluding “er1”, which
represents a non-mainstream concept car model). This also holds
true for MangaTraders with 13 out of the top 20 performing password candidates being related to manga. For Wattpad, the results
are not quite as clear, with many first names and dates appearing in
the top 20 performing candidates e something which is common in
most data leaks (Veras et al., 2012).

time of 15 min was selected for these attacks. A key evaluation point
for the proposed approach is how well each dictionary performs
against stronger, harder-to-crack passwords. It should be
mentioned here that during this 15 min process, more than 10
billion password candidates are evaluated. This is achievable as the
data leaks used for evaluation are in plaintext. To provide an indication of the runtime for this proposed approach for hash-based
password cracking, assuming a Veracrypt full disk encryption was
targeting with an attack leveraging the latest Nvidia RTX 4090 GPU7
running at 6.6 kH/s, evaluating the same number of candidates with
the single GPU would take approximately 20 days.
4.1. Setup of the experiment
Our experiments compare three different dictionaries, namely:
Ignis-10M and the ranked and the unranked version of the dictionaries produced by the seed words in Table 2. Before ranking, both
versions of the unranked dictionary with either whole entities or
split up to individual words, as described in Section 3.5, were
evaluated. The version containing only individual words performed
better and was therefore selected for comparison.
These dictionaries were then evaluated with the same password
mangling rule file. Each rule in the file is a common modification
users choose when they create their passwords, e.g., adding
numbers at the end of their password, replacing some letters with
similar looking numbers, etc. One of the most well-known rulesets
is best64.8 For this experiment, a larger ruleset was chosen,
OneRuleToRuleThemAll.9 This ruleset contains the top 25%
performing rules from several component rulesets, concatenated
together and without duplicates.
Finally, the password cracking was conducted with hashcat10,
which is an open-source password cracking tool.
5. Results
As mentioned in Section 3.2, four datasets stemming from data
leaks centring on cars, music, manga and fanfiction were selected.
For each topic, a contextual dictionary was produced starting from
each seed word, which represents the unranked version. The
ranked version was then produced with the methodology
described above in Section 3. As defined in the previous section, for
three topics, the produced dictionaries were of 3 layers depth and
for Manga, it was 4 layers deep. Manga was selected for an additional layer over the other three, as a three-layered dictionary from
the seed word “manga” was not sufficiently big for this attack (and
indeed performed poorly e especially compared to Ignis-10M).

5.2. Strength of found passwords

5.1. Success over time

Returning to the aforementioned digital forensic triage scenario,
if a digital investigator is looking to crack the password of an
encrypted device belonging to a suspect in a timely manner, looking at the number of passwords cracked per dictionary attack might
not be a sufficiently accurate metric. Ignis-10M, since it is compiled
of some of the most popular passwords from several data leaks, is
assumed to do well with common, popular passwords. But if the
holder of the encrypted device is someone more tech-savvy, reason
states that their password might not be one to be found on these
popular password lists.
In a triage situation, it is therefore important to take into account
the difficulty of the passwords that each dictionary attack successfully cracked. To determining this, the password strength meter
zxcvbn (Wheeler, 2016) was employed. zxcvbn classifies passwords according to their strength and places them in five classes,
ranging from the easiest to crack (Class 0) to the hardest (Class 4).

The cracking progress over time against these four data leaks,
with the baseline Ignis-10M dictionary, the contextual ranked
dictionaries, and the contextual unranked dictionaries can be seen
in Fig. 1(a) to 1(d). As can be seen, the baseline dictionary, Ignis10M, has the best overall performance. This does not come as a
surprise e not only because Ignis-10M is larger and more diverse
than any of the contextual dictionaries, but also because even in a
data leak stemming from a car-related forum, not all passwords
would be car related. Nonetheless, it can still be observed that the
contextual dictionaries perform well, especially the ranked

7

https://www.nvidia.com/en-gb/geforce/graphics-cards/40-series/rtx-4090/.
https://github.com/hashcat/hashcat/blob/master/rules/best64.rule.
9
https://notsosecure.com/one-rule-to-rule-them-all.
10
https://hashcat.net/hashcat/.
8

5

A. Kanta, I. Coisel and M. Scanlon

Forensic Science International: Digital Investigation 44 (2023) 301507

Fig. 1. Number of passwords cracked over time.

This classification for each of the four data leaks with Ignis-10M and
the ranked and unranked dictionaries are shown in Fig. 2.
As can be seen in Fig. 2(a) to 2(d), most of the passwords have
been assigned to Class 1 e with Class 2 being the second most
common. It is generally assumed that the passwords up to Class 2
are easier to crack, and most current password cracking methods
would be able to crack them (Kanta et al., 2021a). Therefore, the
focus is mostly on the passwords belonging to Class 3 and Class 4.
Tables 5 and 6 show the passwords of Class 3 and Class 4
respectively, which were cracked by Ignis-10M, the ranked, and the
unranked context-based dictionaries. It can be observed that once
again, the ranked dictionaries have a better performance compared
to the unranked ones across all four datasets. In fact, in every case
except Class 3 for MangaTraders and Wattpad, the ranked dictionaries have managed to find more exclusive passwords (R Excl
column) than the unranked have managed overall (U column).
When comparing the ranked dictionaries to Ignis-10M, it is
important to notice that the number of passwords found exclusively by the ranked dictionaries, i.e., not found using Ignis-10M, is
quite high. In fact, for Class 3, the increase in password cracking
success rises 20.9%, 27.8%, 15.9% and 20.5% for AxeMusic, JeepForum, Wattpad, and MangaTraders respectively.
Focusing on Class 4, which contains the strongest passwords of
each dataset, on average 50% of those found by the ranked dictionaries are not found using Ignis-10M. In a combination attack, i.e.,
combining the results of the ranked dictionaries and the corresponding results from Ignis-10M, the improvement is 43.4%, 52.3%,
20% and 24.3% for Axe Music, JeepForum, Wattpad, and Manga
Traders respectively.

Table 3
Total number of passwords found. The R Excl. Column contains passwords found
only by ranked dictionaries, The U Excl. Column contains passwords found only by
unranked dictionaries.
Dataset

Ignis-10M

R

R Excl.

U

U Excl.

AxeMusic
JeepForum
Wattpad
MangaTraders

132,009
122,061
4,103,525
352,544

106,782
107,365
3,016,762
289,573

7,773
6,025
268,670
22,128

86,384
89,001
2,367,223
231,097

2,698
2,212
86,267
9,635

Table 4
Top 20 password candidates for the four ranked dictionaries.
Music

Car

Fanfiction

Manga

music
guitar
guitaro
rock
longy
sunshine
piano
love
musical
12
singer
welcome
boy
yamaha
song
blues
drum
guitars
1
rockstar

jeep
dog
man
harley
honda
1
ford
s1
wrangler
chevy
car
camaro
mustang
er1
12
dodge
bike
qwerty
ranger
hummer

love
angel
password
qwerty
100
1997
4ever
bella
1996
monkey
1995
princess
kitty
alex
forever
nicole
lover
girl
hannah
soccer

qwerty
sakura
naruto
pokemon
dragon
manga
inuyasha
angel
sasuke
anime
iloveyou
hello
pikachu
monkey
shadow
chobits
vampire
purple
gundam
akira

6. Discussion
The results of the previous section show the value of considering
context in password cracking. The number of passwords found
6

A. Kanta, I. Coisel and M. Scanlon

Forensic Science International: Digital Investigation 44 (2023) 301507

Fig. 2. Strength of passwords cracked.

focused on specific topics, it is clear that the link between the
password and the purpose of the community is sufficiently present.
This can be seen clearly in Table 4, where the majority of the top
performing password candidates were thematically close to the
seed word/focus of the community.
Furthermore, the process to optimise and rank the contextual
dictionaries has proved fruitful, with the ranked dictionaries outperforming the unranked ones across the board. This is especially
significant in triage-like situations during a digital investigation,
where it is important to gain access to an encrypted device as
quickly as possible. Ranking the dictionary by how similar the
password candidates are to the seed word means that those passwords (and their corresponding permutations with mangling rules)
will be checked first. In a timed attack, as has been the case with the
experiments here, this proves extremely important.
Of course, depending on the specific situation, a combination of
one or more approaches might be needed. For example, depending
on the hash function, an exhaustive search up to 8 digits might be
fast enough to be considered first, followed by a contextual dictionary attack if the “low-hanging fruit approach” does not prove so
fruitful.

Table 5
Class 3 passwords classified using zxcvbn for Ignis-10M, ranked (R) and unranked
(U) dictionaries. The columns R Excl. and U Excl. represent the Class 3 passwords
found exclusively by the R and U dictionaries.

AxeMusic
JeepForum
Wattpad
MangaTraders

Ignis-10M

R

U

R Excl.

U Excl.

7,879
2,039
313,142
21,293

4,003
1,305
137,396
11,739

1,490
491
52,882
5,981

1,645
566
49,742
4,357

393
140
10,400
1,645

Table 6
Class 4 passwords classified using zxcvbn for Ignis, ranked (R) and unranked (U)
dictionaries. The columns R Excl. and U Excl. represent the Class 4 passwords found
exclusively by the R and U dictionaries.

AxeMusic
JeepForum
Wattpad
MangaTraders

Ignis-10M

R

U

R Excl.

U Excl.

551
65
27,005
2,389

380
53
9,346
1,245

118
15
2,628
574

239
34
5,415
581

66
12
1,128
240

exclusively by the unranked and especially the ranked versions of
the contextual dictionaries adds a substantial value to a combination password cracking approach with existing off-the-shelf dictionaries, e.g., Ignis-10M. When cracking the passwords of a large
community focused on a specific topic, a generic dictionary like
Ignis-10M, that contains some of the most popular passwords
found on several data leaks, will always be at an advantage. This is
due to many users choosing passwords that are thematically close
to the purpose of the website the password is for, and many will
still use passwords that either have some personal meaning or
without any contextual meaning at all.
In the presented experiments on data leaks from communities

6.1. Benefits and limitations
As with any approach, there are advantages and limitations. One
of the advantages of the contextual approach is that it is highly
customisable to each suspect. A dictionary can be made with any
starting seed word (as long as there exists a Wikipedia article about
it). This practically means that an investigator could easily have
dictionaries about specific or niche topics at their disposal easily.
These dictionaries can also be highly customisable e the depth of
search can be set by the investigator, and entries that are deemed as
contextually distant to the seed word can be disregarded by
7

A. Kanta, I. Coisel and M. Scanlon

Forensic Science International: Digital Investigation 44 (2023) 301507

tweaking the threshold for the similarity score. Furthermore, dictionaries stemming from different seed words can be combined to
create a combination dictionary.
Another advantage of this approach is that these dictionaries do
not need to be produced again and again for every case. In fact, the
investigator can have on hand dictionaries about frequently
encountered topics and therefore skip the dictionary creation step,
which could again save crucial time during a triage situation.
The importance of these dictionaries hinges on not only the fact
that users tend to form passwords that are meaningful to them,
therefore memorable, but also the highly likely assumption that if a
suspect is tech-savvy enough to use encryption on their devices,
they are also likely to not use easily guessed passwords.
Of course, as with every approach, there are limitations to its
usability. In a scenario where the sheer number of passwords found
is the most important parameter and the runtime and/or strength
of the passwords found is not important, generic dictionaries based
on existing password leaks will most likely perform better. Nonetheless, a combined approach with the technique described as part
of this paper will likely improve the chances of overall success
further.
Furthermore, contextual dictionaries, unlike common password
lists such as Ignis-10M and RockYou, are lists of words not lists of
passwords. Mangling rules can help remedy this to an extent, but it
is safe to say that many words that can have a high similarity score
to the seed word and therefore be placed high during the ranking
are not words that would be used to create a password. One such
example is the word “series”. Using a contextual dictionary with
phrases and the proposed ranking approach, “Manga Series” has a
similarity score of 1 compared to “Manga” (1 for “Manga” and 0.54
for “Series”), which would place it at the top of the list. But in reality, the phrase “Manga Series” is not as likely to be a password as
the names of actual manga series, as evidenced in Table 4.

good starting point for future work on the topic. In fact, more
attention should be given into filtering the password candidates
such that candidates with high similarity to the seed word, but low
probability of being used as passwords, can be filtered out. A potential way to do this would be to look at the bidirectional distance
between these two words. For example, is “Series” as close to
“Manga” as “Manga” is to “Series”? Or, is the number of words that
are thematically closer to “Manga” than “Series” the same for “Series” to “Manga”? To this end, looking back at Layer n-1 might also
prove useful, as it will contain links that link back to “Manga”.
Furthermore, even though the contextual dictionaries without
phrases outperformed those containing phrases, it is possible that
contextual information is going to be lost by not also keeping
phrases together. For example, in a contextual dictionary with the
seed word of “Manga”, “ManofSteel” is more likely to be someone’s
password than the individual words “man” and “steel”. At the same
time, there are phrase entries that do not warrant further consideration, e.g., the link “List of Manga Series”, which is a Wikipedia
display construct for storing similar content, but is not a valid
candidate phrase by itself. Therefore, a more robust sanitation
process could greatly benefit the success of the contextual dictionaries. This sanitation process could again be based on NLP, with
the similarity of the words within the phrase to each other being
taken into account to further refine the password candidates
extracted.
References
Avoine, G., Carpent, X., Leblanc-Albarel, D., 2021. Precomputation for rainbow tables
has never been so fast. In: Bertino, E., Shulman, H., Waidner, M. (Eds.), Computer Security e ESORICS 2021. Springer International Publishing, Cham, ISBN
978-3-030-88428-4, pp. 215e234.
Bonneau, J., Herley, C., Oorschot, P.C.v., Stajano, F., 2012a. The quest to replace
passwords: a framework for comparative evaluation of web authentication
schemes. In: 2012 IEEE Symposium on Security and Privacy, pp. 553e567.
https://doi.org/10.1109/SP.2012.44.
Bonneau, J., Shutova, E., 2012b. Linguistic properties of multi-word passphrases. In:
Blyth, J., Dietrich, S., Camp, L.J. (Eds.), Financial Cryptography and Data Security.
Springer Berlin Heidelberg, Berlin, Heidelberg, ISBN 978-3-642-34638-5,
pp. 1e12.
Bosnjak, L., Sres, J., Brumen, B., 2018. Brute-force and dictionary attack on hashed
real-world passwords. In: 2018 41st International Convention on Information
and Communication Technology, Electronics and Microelectronics. MIPRO,
pp. 1161e1166. https://doi.org/10.23919/MIPRO.2018.8400211.
Castelluccia, C., Dürmuth, M., Perito, D., 2012. Adaptive Password-Strength Meters
from Markov Models. NDSS.
 de Carnavalet, X., Mannan, M., 2014. From very weak to very strong:
de Carne
analyzing password-strength meters. In: Network and Distributed System Security (NDSS) Symposium 2014. Internet Society (in press). https://spectrum.
library.concordia.ca/id/eprint/978105/;.
Du, X., Hargreaves, C., Sheppard, J., Anda, F., Sayakkara, A., Le-Khac, N.A.,
Scanlon, M., 2020. SoK: Exploring the state of the art and the future potential of
artificial intelligence in digital forensic investigation. In: Proceedings of the
15th International Conference on Availability, Reliability and Security. Association of Computing Machinery, ISBN 9781450388337. https://doi.org/10.1145/
3407023.3407068.
Dürmuth, M., Angelstorf, F., Castelluccia, C., Perito, D., Chaabane, A., 2015. Omen:
faster password guessing using an ordered markov enumerator. In: Piessens, F.,
Caballero, J., Bielova, N. (Eds.), Engineering Secure Software and Systems.
Springer International Publishing, Cham, ISBN 978-3-319-15618-7, pp. 119e132.
Florencio, D., Herley, C., 2007. A large-scale study of web password habits. In:
Proceedings of the 16th International Conference on World Wide Web. Association for Computing Machinery, pp. 657e666. https://doi.org/10.1145/
1242572.1242661.
Grassi, P.A., Fenton, J.L., Newton, E.M., Perlner, R.A., Regenscheid, A.R., Burr, W.E.,
Richer, J.P., Lefkovitz, N.B., Danker, J.M., Choong, Y.Y., Greene, K.K.,
Theofanos, M.F., 2017. NIST Special Publication 800-63B - Digital Identity
Guidelines: Authentication and Lifecycle Management. Tech. Rep. National
Institute for Standards and Technology. https://doi.org/10.6028/NIST.SP.80063b.
Guo, Y., Zhang, Z., 2018. Lpse: lightweight password-strength estimation for password meters. Computers and Security, 73, 507e518. https://doi.org/10.1016/
j.cose.2017.07.012. URL: https://www.sciencedirect.com/science/article/pii/
S0167404817301530.
Hitaj, B., Gasti, P., Ateniese, G., Perez-Cruz, F., 2019. PassGAN: a deep learning
approach for password guessing. In: Applied Cryptography and Network

7. Conclusion and future work
The contribution offers the outline for a methodology for
creating custom dictionary lists on any choice of topics, ones that
can be useful to a digital investigator for cracking the password of
an encrypted device. This methodology leverages natural language
processing to create bespoke dictionary lists. The entries are ranked
in descending order of similarity to the seed word that was used to
create the dictionary, with the aim to try the most likely password
candidates first. This is especially useful when the timely access to
an encrypted device is of the essence, as the candidates with the
highest similarity score will be checked first.
As outlined in Section 5, the use of these contextual dictionaries
can compete with much larger and variant dictionary lists, such as
Ignis-10M, can offer a significant increase in found passwords if the
generic and contextual approach are combined. The contribution of
the contextual dictionaries is particularly important for Class 3 and
Class 4 passwords, where the increase in found passwords by adding
the ranked contextual dictionary in addition to Ignis-10M resulted in
as many as 50% more passwords found. This is especially significant
considering how the size of the bespoke dictionaries is much smaller
to more well-rounded password dictionary lists.
For a digital forensic investigation, pre-computed bespoke dictionaries can be a very useful tool for an investigator as they
perform well against harder to crack passwords and their length,
depth and relevancy to the seed word can be easily customised by
the investigator as needed.
7.1. Future work
Addressing some of the limitations outlined in Section 6.1 is a
8

A. Kanta, I. Coisel and M. Scanlon

Forensic Science International: Digital Investigation 44 (2023) 301507
Companion Proceedings For the ISSTA/ECOOP 2018 Workshops. ISSTA ’18. Association for Computing Machinery, New York, NY, USA, ISBN 9781450359399,
pp. 138e143. https://doi.org/10.1145/3236454.3236512. URL:
Shay, R., Bauer, L., Christin, N., Cranor, L.F., Forget, A., Komanduri, S., Mazurek, M.L.,
Melicher, W., Segreti, S.M., Ur, B., 2015. A spoonful of sugar? the impact of
guidance and feedback on password-creation behavior. In: Proceedings of the
33rd Annual ACM Conference on Human Factors in Computing Systems,
pp. 2903e2912.
Ur, B., Noma, F., Bees, J., Segreti, S.M., Shay, R., Bauer, L., Christin, N., Cranor, L.F.,
2015. ”I added ’!’ at the end to make it secure”: observing password creation in
the lab. In: Eleventh Symposium on Useable Privacy and Security. SOUPS 2015,
pp. 123e140.
Ur, B., Bees, J., Segreti, S.M., Bauer, L., Christin, N., Cranor, L.F., 2016. Do users’ perceptions of password security match reality?. In: Proceedings of the 2016 CHI
Conference on Human Factors in Computing Systems. CHI ’16;. Association for
Computing Machinery, New York, NY, USA, ISBN 9781450333627,
pp. 3748e3760. https://doi.org/10.1145/2858036.2858546. URL:
Veras, R., Thorpe, J., Collins, C., 2012. Visualizing semantics in passwords: the role of
dates. In: Proceedings of the Ninth International Symposium on Visualization
for Cyber Security. VizSec ’12. Association for Computing Machinery, New York,
NY, USA, ISBN 9781450314138, pp. 88e95. https://doi.org/10.1145/
2379690.2379702. URL:
Wang, D., Zhang, Z., Wang, P., Yan, J., Huang, X., 2016. Targeted online password
guessing: an underestimated threat. In: Proceedings of the 2016 ACM SIGSAC
Conference on Computer and Communications Security. CCS ’16. Association for
Computing Machinery, New York, NY, USA, ISBN 9781450341394,
pp. 1242e1254. https://doi.org/10.1145/2976749.2978339. URL:
Wang, D., Cheng, H., Wang, P., Huang, X., Jian, G., 2017. Zipf’s law in passwords. IEEE
Trans. Inf. Forensics Secur. 12 (11), 2776e2791. https://doi.org/10.1109/
TIFS.2017.2721359.
Wash, R., Rader, E., Berman, R., Wellmer, Z., 2016a. Understanding password
choices: how frequently entered passwords are Re-used across websites. In:
Twelfth Symposium on Useable Privacy and Security (SOUPS 2016). USENIX
Association, Denver, CO, ISBN 978-1-931971-31-7, pp. 175e188. URL: https://
www.usenix.org/conference/soups2016/technical-sessions/presentation/wash.
Wash, R., Rader, E., Berman, R., Wellmer, Z., 2016b. Understanding password
choices: how frequently entered passwords are re-used across websites. In:
Twelfth Symposium on Useable Privacy and Security. SOUPS 2016, pp. 175e188.
Weir, M., Aggarwal, S., Medeiros, B.d., Glodek, B., 2009. Password cracking using
probabilistic context-free grammars. In: 2009 30th IEEE Symposium on Security and Privacy, pp. 391e405. https://doi.org/10.1109/SP.2009.8.
Wheeler, D.L., 2016. zxcvbn: Low-budget password strength estimation. In: 25th
USENIX Security Symposium, vol. 16. USENIX Security, pp. 157e173.
Yamada, I., Asai, A., Sakuma, J., Shindo, H., Takeda, H., Takefuji, Y., Matsumoto, Y.,
2020. Wikipedia2Vec: An efficient toolkit for learning and visualizing the embeddings of words and entities from Wikipedia. In: Proceedings of the 2020
Conference on Empirical Methods in Natural Language Processing: System
Demonstrations. Association for Computational Linguistics, pp. 23e30.

Security. Springer, pp. 217e237.
Kanta, A., Coisel, I., Scanlon, M., 2020a. A survey exploring open source intelligence
for smarter password cracking. Forensic Sci. Int.: Digit. Invest. 35, 301075.
https://doi.org/10.1016/j.fsidi.2020.301075. ISSN 2666-2817.
Kanta, A., Coisel, I., Scanlon, M., 2020b. Smarter password guessing techniques
leveraging contextual information and OSINT. In: 2020 International Conference on Cyber Security and Protection of Digital Services (Cyber Security), vols.
1e2. IEEE.
Kanta, A., Coray, S., Coisel, I., Scanlon, M., 2021a. How viable is password cracking in
digital forensic investigation? Analyzing the guessability of over 3.9 billion realworld accounts. Forensic Sci. Int. Digit. Invest. 37, 301186. https://doi.org/
10.1016/j.fsidi.2021.301186. ISSN 2666-2817.
Kanta, A., Coisel, I., Scanlon, M., 2021b. PCWQ: a framework for evaluating password
cracking wordlist quality. In: The 12th EAI International Conference On Digital
Forensics And Cyber Crime. ICDF2C ’21. Springer, New York, NY, USA.
Kanta, A., Coisel, I., Scanlon, M., 2022. A novel dictionary generation methodology
for contextual-based password cracking. IEEE Access 10, 59178e59188. https://
doi.org/10.1109/ACCESS.2022.3179701.
Li, Y., Wang, H., Sun, K., 2017. Personal information in passwords and its security
implications. IEEE Trans. Inf. Forensics Secur. 12 (10), 2320e2333.
Melicher, W., Ur, B., Segreti, S.M., Komanduri, S., Bauer, L., Christin, N., Cranor, L.F.,
2016. Fast, lean, and accurate: Modeling password guessability using neural
networks. In: 25th USENIX Security Symposium (USENIX Security 16). USENIX
Association, Austin, TX, ISBN 978-1-931971-32-4, pp. 175e191. URL: https://
www.usenix.org/conference/usenixsecurity16/technical-sessions/presentation/
melicher.
Mikolov, T., Chen, K., Corrado, G.S., Dean, J., 2013. Efficient estimation of word
representations in vector space. URL: http://arxiv.org/abs/1301.3781.
Narayanan, A., Shmatikov, V., 2005. Fast dictionary attacks on passwords using
time-space tradeoff. In: Proceedings of the 12th ACM Conference on Computer
and Communications Security. CCS ’05. Association for Computing Machinery,
New York, NY, USA, ISBN 1595932267, pp. 364e372. https://doi.org/10.1145/
1102120.1102168. URL:
Oechslin, P., 2003. Making a faster cryptanalytic time-memory trade-off. In:
Boneh, D. (Ed.), Advances in Cryptology - CRYPTO 2003. Springer Berlin Heidelberg, Berlin, Heidelberg, ISBN 978-3-540-45146-4, pp. 617e630.
Pal, B., Daniel, T., Chatterjee, R., Ristenpart, T., 2019. Beyond credential stuffing:
password similarity models using neural networks. In: 2019 IEEE Symposium
on Security and Privacy. SP, pp. 417e434. https://doi.org/10.1109/SP.2019.00056.
Pasquini, D., Ateniese, G., Bernaschi, M., 2020. Interpretable probabilistic password
strength meters via deep learning. In: Chen, L., Li, N., Liang, K., Schneider, S.
(Eds.), Computer Security e ESORICS 2020. Springer International Publishing,
Cham, ISBN 978-3-030-58951-6, pp. 502e522.
Ryder, S., Le-Khac, N.A., 2016. The end of effective law enforcement in the cloud? to encrypt, or not to encrypt. In: 2016 IEEE 9th International Conference on
Cloud
Computing.
CLOUD,
pp.
904e907.
https://doi.org/10.1109/
CLOUD.2016.0133.
Sayakkara, A., Le-Khac, N.A., Scanlon, M., 2018. Electromagnetic side-channel attacks: Potential for progressing hindered digital forensic analysis. In:

9
