🛡️ UBUNTU-CVE-2021-4126
⚪ Unknown ✅ No Known Exploit OSV
N/A
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

When receiving an OpenPGP/MIME signed email message that contains an additional outer MIME message layer, for example a message footer added by a mailing list gateway, Thunderbird only considered the inner signed message for the signature validity. This gave the false impression that the additional contents were also covered by the digital signature. Starting with Thunderbird version 91.4.1, only the signature that belongs to the top level MIME part will be considered for the displayed status. This vulnerability affects Thunderbird < 91.4.1.

Details

Severity Unknown
CVSS Score N/A
CVSS Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
CWE N/A
Public Exploit ✅ No
Source OSV
Published 2021-12-24
Updated 2026-06-15
Modified 2026-04-22
Fix URL N/A

Affected Packages

Software From version Fixed in
thunderbird 1:91.5.0+build1-0ubuntu1

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