Description
An attacker could cause a heap buffer overflow by getting a user to open an email that is greater than or equal to 2GB in size. This vulnerability was fixed in Thunderbird 157, Thunderbird 140.17, and Thunderbird 153.4.
Affected products
mozilla: thunderbird
References4
- www.mozilla.org/security/advisories/mfsa2026-101/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-102/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-103/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=2070267 Permissions Required
Metrics
- CVSS 3.1
-
6.1
MEDIUM
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H - EPSS — exploit probability
- 0% percentile: 20 · as of 10 November 2026
- CWE
- CWE-787CWE-122
Could this be exploited in your environment?
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