CVE-2026-14899 (GCVE-0-2026-14899)
Vulnerability from cvelistv5
Published
2026-07-22 19:19
Modified
2026-07-27 17:12
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Summary
The code to parse MIME headers for display when forwarding a message (if the setting to view all headers was enabled) had an off-by-one error, allowing a single byte to be read from the memory after the buffer for the headers, and potentially crashing Thunderbird. This vulnerability was fixed in Thunderbird 153 and Thunderbird 140.13.
References
Impacted products
Vendor Product Version
Mozilla Thunderbird Unaffected: 140.13
Unaffected: 153
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