CVE-2026-92239
A maliciously constructed IMAP line could cause an out-of-bounds buffer read. This vulnerability was fixed in Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.
- Published Sep 15, 2026
- CVSS 8.1 high
- 0.4% chance of exploitation in the next 30 days (EPSS)
- A fix is available