Related Vulnerabilities: CVE-2021-23992  

Thunderbird before version 78.9.1 did not check if the user ID associated with an OpenPGP key has a valid self signature. An attacker may create a crafted version of an OpenPGP key, by either replacing the original user ID, or by adding another user ID. If Thunderbird imports and accepts the crafted key, the Thunderbird user may falsely conclude that the false user ID belongs to the correspondent.

Severity Medium

Remote Yes

Type Signature forgery

Description

Thunderbird before version 78.9.1 did not check if the user ID associated with an OpenPGP key has a valid self signature. An attacker may create a crafted version of an OpenPGP key, by either replacing the original user ID, or by adding another user ID. If Thunderbird imports and accepts the crafted key, the Thunderbird user may falsely conclude that the false user ID belongs to the correspondent.

AVG-1790 thunderbird 78.9.0-1 Medium Vulnerable

https://www.mozilla.org/en-US/security/advisories/mfsa2021-13/#CVE-2021-23992
https://bugzilla.mozilla.org/show_bug.cgi?id=1666236