CVE-2026-84641 (GCVE-0-2026-84641)

Vulnerability from cvelistv5 – Published: 2026-09-01 21:33 – Updated: 2026-09-02 18:47
VLAI
Title
Information disclosure due to malicious IMAP server response
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-02 18:44 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
Mozilla Thunderbird Unaffected: 140.15 , ≤ 140.* (rpm)
Unaffected: 153.2 , ≤ 153.* (rpm)
Unaffected: 155 , ≤ * (rpm)
guessed Create a notification for this product.
Credits
ABDULAZIZ ALASAIQAH
Show details on NVD website
To clipboard 

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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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