| Recurring |
one_organization, multiple_organization |
(a) The software failure incident related to the vulnerability in PGP and S/MIME encryption schemes has happened again at the same organization or with its products and services. The incident was specifically related to a serious vulnerability in PGP encryption, as reported by researchers from Munster University of Applied Sciences [71108, 71263].
(b) The software failure incident has also happened at multiple organizations or with their products and services. The vulnerability in PGP encryption was a widespread issue affecting various email clients that use PGP for encryption, as highlighted by the Electronic Frontier Foundation (EFF) and other security experts [71108, 71263]. |
| Phase (Design/Operation) |
design, operation |
(a) The software failure incident related to the design phase is evident in the articles. The vulnerability in PGP and S/MIME encryption schemes, known as eFail, was due to weaknesses in how email clients processed HTML elements in encrypted messages. Attackers could manipulate the HTML elements to expose plaintext versions of encrypted messages, highlighting a flaw in the design of the encryption systems [71108, 71263].
(b) The software failure incident related to the operation phase is also apparent. The vulnerability in PGP emails was exploited by attackers through email programs that failed to check for decryption errors properly before following links in emails containing HTML code. This operational flaw allowed for the attack on PGP emails to occur, emphasizing issues with the operation or misuse of the system [71263]. |
| Boundary (Internal/External) |
within_system, outside_system |
(a) within_system: The software failure incident related to the PGP and S/MIME encryption schemes vulnerability, known as eFail, is primarily within the system. The vulnerability arises from how the email clients decrypt encrypted messages and process HTML elements, allowing attackers to manipulate the message content and extract plaintext. The weakness is inherent to the design and implementation of the encryption schemes and how email clients handle decryption and rendering of messages [71108, 71263].
(b) outside_system: The software failure incident also involves factors originating from outside the system. For example, the attack requires the attacker to intercept encrypted messages before manipulating them, indicating an external interception of communication channels. Additionally, the vulnerability could potentially allow attackers to decrypt a cache of encrypted emails sent in the past if they have access to such data, suggesting a threat from external sources [71263]. |
| Nature (Human/Non-human) |
non-human_actions, human_actions |
(a) The software failure incident in the articles is primarily due to non-human actions. The vulnerability in the PGP and S/MIME encryption schemes, known as eFail, allows attackers to manipulate how encrypted emails process HTML elements, leading to the exposure of plaintext versions of messages [71108]. The vulnerability was found in the core protocol of PGP, affecting email programs that failed to check for decryption errors properly before following links in emails containing HTML code [71263].
(b) However, human actions also played a role in the failure. The issue was initially overblown by the Electronic Frontier Foundation (EFF), which advised immediately disabling email tools that automatically decrypted PGP, causing concern among cybersecurity researchers [71263]. Additionally, the vulnerability could be used by attackers to decrypt a cache of encrypted emails sent in the past if they had access to such data, highlighting the potential risks associated with human actions in managing encrypted communications [71263]. |
| Dimension (Hardware/Software) |
hardware, software |
(a) The software failure incident occurring due to hardware:
- The vulnerability in PGP and S/MIME encryption schemes, known as eFail, was due to an attacker manipulating how the message processes its HTML elements, like images and multimedia styling, which could expose plaintext versions of encrypted messages [71108].
- The vulnerability in PGP emails specifically concerned email programs that failed to check for decryption errors properly before following links in emails that included HTML code, indicating a flaw in the email programs' hardware-related processes [71263].
(b) The software failure incident occurring due to software:
- The weakness in PGP and S/MIME encryption schemes, leading to the eFail attack, was a software-related vulnerability that allowed attackers to grab plaintext of encrypted messages by manipulating HTML elements in the message [71108].
- The vulnerability in PGP emails was not a flaw in the OpenPGP system itself but rather in email programs that had been designed without appropriate safeguards, indicating a software-related issue [71263]. |
| Objective (Malicious/Non-malicious) |
malicious, non-malicious |
(a) The software failure incident related to the PGP and S/MIME encryption schemes vulnerability, known as eFail, can be categorized as malicious. The vulnerability allowed attackers to manipulate encrypted emails to expose plaintext versions of the messages, posing a significant threat to users' privacy and security [71108].
(b) On the other hand, the vulnerability in PGP emails, as reported by researchers, was not considered a vulnerability in the OpenPGP system itself but rather in email programs that lacked appropriate safeguards. This indicates a non-malicious software failure incident where the issue was due to the design flaws in the email programs rather than intentional harm [71263]. |
| Intent (Poor/Accidental Decisions) |
poor_decisions |
(a) The intent of the software failure incident:
- The software failure incident related to the PGP and S/MIME encryption schemes vulnerability, known as eFail, was not due to accidental decisions but rather poor decisions. The vulnerability emerged when an attacker manipulated how the message processed its HTML elements, allowing them to grab the plaintext of the message [71108].
- The issue with PGP emails was specifically related to email programs that failed to check for decryption errors properly before following links in emails that included HTML code, indicating a poor decision in the design of these email programs [71263]. |
| Capability (Incompetence/Accidental) |
development_incompetence, accidental |
(a) The software failure incident related to the PGP and S/MIME encryption schemes vulnerability, known as eFail, can be attributed to development incompetence. The weakness in the encryption schemes allowed a hacker to expose plaintext versions of encrypted messages by manipulating how the message processes its HTML elements [71108]. Additionally, the vulnerability in PGP emails was found to be a serious flaw, with concerns that the issue affected the core protocol of PGP, potentially making all uses of the encryption method vulnerable [71263].
(b) The software failure incident can also be considered accidental as the vulnerability in PGP emails was not initially recognized as a vulnerability in the OpenPGP system itself but rather in email programs that had been designed without appropriate safeguards [71263]. This indicates that the vulnerability was not intentionally introduced but rather a result of oversight or lack of proper implementation practices. |
| Duration |
temporary |
The software failure incident related to the PGP and S/MIME encryption schemes vulnerability, known as eFail, can be considered a temporary failure. This is because the vulnerability arises from specific circumstances where an attacker manipulates how encrypted emails process HTML elements, allowing them to grab plaintext messages. The incident is not a permanent failure as it is not a fundamental flaw in the encryption schemes themselves but rather a vulnerability in email programs that fail to check for decryption errors properly before following links in emails with HTML code [71108, 71263]. |
| Behaviour |
omission, value, other |
(a) crash: The software failure incident described in the articles does not involve a crash where the system loses state and does not perform any of its intended functions.
(b) omission: The vulnerability in PGP and S/MIME email encryption schemes allowed attackers to manipulate encrypted emails, leading to the exposure of plaintext versions of messages. This can be considered a failure due to the system omitting to perform its intended function of securely encrypting and protecting email content [71108, 71263].
(c) timing: The incident does not involve a failure related to the system performing its intended functions too late or too early.
(d) value: The vulnerability in the PGP and S/MIME encryption schemes resulted in the system performing its intended function of encryption incorrectly, leading to the exposure of plaintext messages. This can be categorized as a failure due to the system performing its intended functions incorrectly [71108, 71263].
(e) byzantine: The software failure incident does not exhibit behavior of the system behaving erroneously with inconsistent responses and interactions.
(f) other: The other behavior observed in this software failure incident is the system failing to properly check for decryption errors and following links in emails that included HTML code, which ultimately led to the vulnerability being exploited. This can be considered a failure due to the system behaving in a way that lacks appropriate safeguards [71263]. |