CVE-2026-94184
A stack-based buffer overflow flaw was found in fetchmail when built with NTLM support. A malicious or compromised mail server advertising NTLM authentication can send a crafted Type 2 challenge that causes fetchmail to write past a fixed stack buffer while building the NTLM authenticate response. This may lead to remote code execution depending on stack-frame layout, or to authentication failure or process termination under memory hardening. Affects v5.0.8 through v6.6.6.
Weakness
A stack-based buffer overflow flaw was found in fetchmail when built with NTLM support. A malicious or compromised mail server advertising NTLM authentication can send a crafted Type 2 challenge that causes fetchmail to write past a fixed stack buffer while building the NTLM authenticate response. This may lead to remote code execution depending on stack-frame layout, or to authentication failure or process termination under memory hardening. Affects v5.0.8 through v6.6.6.
References
- https://access.redhat.com/security/cve/CVE-2026-94184
- https://bugzilla.redhat.com/show_bug.cgi?id=2537395
- https://gitlab.com/fetchmail/fetchmail/-/commit/cb5be5c38471eec19e519ace0bc569176317ea92
- https://www.fetchmail.info/fetchmail-SA-2026-01.txt
- https://www.openwall.com/lists/oss-security/2026/06/27/8
- http://www.openwall.com/lists/oss-security/2026/09/23/1
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