CVE-2026-84641: Vulnerability in Mozilla Thunderbird
A malicious IMAP server can trigger use-after-free and heap-memory disclosure by sending a crafted ID response. Heap contents can ultimately be persisted to prefs.js. This vulnerability was fixed in Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.
CVE-2026-84641: Vulnerability in Mozilla Thunderbird
Description
A malicious IMAP server can trigger use-after-free and heap-memory disclosure by sending a crafted ID response. Heap contents can ultimately be persisted to prefs.js. This vulnerability was fixed in Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-09-01T21:33:07.129Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-86/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-87/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-88/","vendor":"Mozilla"}]
Threat ID: 6a97492dacd9273b493ed28c
Added to database: 09/01/2026, 21:52:45 UTC
Last updated: 09/02/2026, 02:12:46 UTC
Views: 9
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