CVE-2026-94184

high

Description

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://www.openwall.com/lists/oss-security/2026/06/27/8

https://www.fetchmail.info/fetchmail-SA-2026-01.txt

https://gitlab.com/fetchmail/fetchmail/-/commit/cb5be5c38471eec19e519ace0bc569176317ea92

https://bugzilla.redhat.com/show_bug.cgi?id=2537395

https://access.redhat.com/security/cve/CVE-2026-94184

http://www.openwall.com/lists/oss-security/2026/09/23/1

Details

Source: Mitre, NVD

Published: 2026-09-21

Updated: 2026-09-23

Risk Information

CVSS v2

Base Score: 7.6

Vector: CVSS2#AV:N/AC:H/Au:N/C:C/I:C/A:C

Severity: High

CVSS v3

Base Score: 8.1

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Severity: High

EPSS

EPSS: 0.00665