DEBIAN-CVE-2026-4371

Advisory lineage Upstream: 1 Downstream: 2
Upstream
CVE-2026-4371
Published: 24 Mar 2026, 21:16
Last modified:28 Apr 2026, 20:31

Vulnerability Summary

Overall Risk (default)
medium
30/100
CVSS Score
7.4 HIGH
3.1 (osv_debian)
EPSS Score
No data
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

24 Mar 2026, 21:16
Published
Vulnerability first disclosed
28 Apr 2026, 20:31
Last Modified
Vulnerability information updated

Description

A malicious mail server could send malformed strings with negative lengths, causing the parser to read memory outside the buffer. If a mail server or connection to a mail server were compromised, an attacker could cause the parser to malfunction, potentially crashing Thunderbird or leaking sensitive data. This vulnerability was fixed in Thunderbird 149 and Thunderbird 140.9.

CVSS Metrics

  • v3.1•HIGH•Score: 7.4CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H

Affected Systems

  • debian•thunderbird

    all | all | all | all | < 1:140.9.0esr-1~deb11u1 | < 1:140.9.0esr-1~deb12u1 | < 1:140.9.0esr-1~deb13u1 | < 1:140.9.0esr-1

References (1)