CVE-2026-4371 (GCVE-0-2026-4371)
Vulnerability from cvelistv5
Published
2026-03-24 20:27
Modified
2026-04-13 13:51
Severity ?
7.4 (High) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H
Summary
A malicious mail server could send malformed strings with negative lengths, causing the parser to read memory outside the buffer. If a mail server or connection to a mail server were compromised, an attacker could cause the parser to malfunction, potentially crashing Thunderbird or leaking sensitive data. This vulnerability was fixed in Thunderbird 149 and Thunderbird 140.9.
References
Impacted products
Vendor Product Version
Mozilla Thunderbird Unaffected: 140.9
Unaffected: 149
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