CVE-2025-26696: Mozilla Thunderbird · CWE-290
Affects Mozilla ThunderbirdSource CVE Database V5
Not known to be exploited · CVSS 7.0 High : upgrade to 136 or 128.8 soon.
Data as of 26 Oct 2026, 10:12 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 29% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 136, 128.8
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:LExploitation evidence
Disclosed: evidence found.
CVE published 10 Mar 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade Mozilla Thunderbird to 136 or 128.8.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Mozilla Thunderbird | Affected
| Fixed in
|
AI-suggested
This vulnerability has been fixed in Mozilla Thunderbird versions 136 and ESR 128.8. Users and administrators should upgrade to these versions or later to remediate the issue. The vendor advisories explicitly confirm the availability of these fixes. No additional mitigation steps are required beyond applying the official updates. Since scripting is disabled when reading mail, exploitation through email is limited. Verify that Thunderbird installations are updated to at least version 136 or 128.8 ESR to ensure protection.
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.