CVE-2026-126134 mozilla thunderbird
mozilla thunderbird: no CVSS score yet. EPSS 0.2% estimated probability of exploitation activity in the next 30 days.
On this page
Thunderbird allowed feed subscriptions to file: URLs that point to a network share. If a user was tricked into subscribing to such a URL, Thunderbird connected to the attacker's server when fetching the feed. Windows then sent the user's NTLM credentials to that server.
This bug only affects Thunderbird on Windows. Other operating systems are unaffected. This vulnerability was fixed in Thunderbird 160 and Thunderbird 153.7.
- EPSS
- 0.2% estimated probability of exploitation activity in the next 30 days; 9th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- Published
- Modified
- Assigned by
- mozilla (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Affected
Versions
From the CNA's record in the CVE List.
Fixed in
| Product | Release line | Fixed in |
|---|---|---|
| Mozilla Thunderbird | 153 | 153.7 |
| Mozilla Thunderbird | later releases | 160 |
Fix and patched versions
- Mozilla Thunderbird: fixed in 153.7
- Mozilla Thunderbird: fixed in 160
- Debian: fixed package versions per release
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Debian | 12 | thunderbird | 1:153.7.0esr-1~deb12u1 | DEBIAN-CVE-2026-126134 |
| Debian | 13 | thunderbird | 1:153.7.0esr-1~deb13u1 | DEBIAN-CVE-2026-126134 |
| Debian | 14 | thunderbird | no fix listed | DEBIAN-CVE-2026-126134 |
| Ubuntu | 22.04:LTS, 24.04:LTS, 26.04:LTS and 1 more | thunderbird | no fix listed | UBUNTU-CVE-2026-126134 |
From the distributions' data via OSV.dev: the Debian Security Tracker; Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Debian · Ubuntu.