CVE-2022-1520: Mozilla Thunderbird

Medium severity, CVSS 4.3. EPSS: 0.3% chance of exploitation in the next 30 days.

When viewing an email message A, which contains an attached message B, where B is encrypted or digitally signed or both, Thunderbird may show an incorrect encryption or signature status. After opening and viewing the attached message B, when returning to the display of message A, the message A might be shown with the security status of message B. This vulnerability affects Thunderbird < 91.9.

Affected products

• Mozilla Thunderbird: before 91.9 (fixed in 91.9)

Published 2022-12-22. Last modified 2026-06-17.