Mutt
CVE-2020-14954
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A05:2025 - Injection
ASVS 5.0
V1 - Encoding and Sanitization Input neutralization, injection prevention
|
| Impact | CVSS score of 5.9 (MEDIUM). Attack characteristics: network attack vector, high complexity, no privileges required, no user interaction not required. |
| Exploit ScenarioDerived | This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the medium-severity affected system. |
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Alert meAnalysisAI
Mutt before 1.14.4 and NeoMutt before 2020-06-19 have a STARTTLS buffering issue that affects IMAP, SMTP, and POP3. Rated medium severity (CVSS 5.9), this vulnerability is remotely exploitable, no authentication required.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
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Technical ContextAI · show details
This vulnerability is classified under CWE-74. Mutt before 1.14.4 and NeoMutt before 2020-06-19 have a STARTTLS buffering issue that affects IMAP, SMTP, and POP3. When a server sends a "begin TLS" response, the client reads additional data (e.g., from a man-in-the-middle attacker) and evaluates it in a TLS context, aka "response injection." Affected products include: Mutt, Debian Debian Linux, Neomutt, Fedoraproject Fedora, Canonical Ubuntu Linux. Version information: before 1.14.4.
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Severity by source
AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
Mutt before 1.14.4 and NeoMutt before 2020-06-19 have a STARTTLS buffering issue that affects IMAP, SMTP, and POP3. When a server sends a "begin TLS" response, the client reads additional data (e.g., from a man-in-the-middle attacker) and evaluates it in a TLS context, aka "response injection."
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Code injection occurs when an application accepts user input and passes it directly into a language interpreter or evaluator without proper sanitization.
Affected Products (CPE)NVD
An issue was discovered in Mutt before 1.10.1 and NeoMutt before 2018-07-16. Rated critical severity (CVSS 9.8), this vu
An issue was discovered in Mutt before 1.10.1 and NeoMutt before 2018-07-16. Rated critical severity (CVSS 9.8), this vu
An issue was discovered in Mutt before 1.10.1 and NeoMutt before 2018-07-16. Rated critical severity (CVSS 9.8), this vu
An issue was discovered in Mutt before 1.10.1 and NeoMutt before 2018-07-16. Rated critical severity (CVSS 9.8), this vu
An issue was discovered in Mutt before 1.10.1 and NeoMutt before 2018-07-16. Rated critical severity (CVSS 9.8), this vu
An issue was discovered in Mutt before 1.10.1 and NeoMutt before 2018-07-16. Rated critical severity (CVSS 9.8), this vu
An issue was discovered in Mutt before 1.10.1 and NeoMutt before 2018-07-16. Rated critical severity (CVSS 9.8), this vu
An issue was discovered in Mutt before 1.10.1 and NeoMutt before 2018-07-16. Rated critical severity (CVSS 9.8), this vu
An issue was discovered in Mutt before 1.10.1 and NeoMutt before 2018-07-16. Rated critical severity (CVSS 9.8), this vu
An issue was discovered in Mutt before 1.10.1 and NeoMutt before 2018-07-16. Rated critical severity (CVSS 9.8), this vu
An issue was discovered in Mutt before 1.10.1 and NeoMutt before 2018-07-16. Rated critical severity (CVSS 9.8), this vu
The write_one_header function in mutt 1.5.23 does not properly handle newline characters at the beginning of a header, w
NVD
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EPSS
GitHub
Exploit-DB