CVE-2025-26696
This vulnerability was fixed in Thunderbird 136 and Thunderbird 128.8.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.36%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Certain crafted MIME email messages that claimed to contain an encrypted OpenPGP message, which instead contained an OpenPGP signed message, were wrongly shown as being encrypted. This vulnerability was fixed in Thunderbird 136 and Thunderbird 128.8.
- CVSS 3.1
- 7.0 HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:L
- EPSS
- 0.36% probability · 29th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-290
- Affected
- mozilla/thunderbird
- Source
- security@mozilla.org
EPSS 0.4% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1864205Issue Tracking
- https://www.mozilla.org/security/advisories/mfsa2025-17/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-18/Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.