CVE-2025-26465

Published: Feb 18, 2025

Modified: May 12, 2026

PUBLISHED

CVSS v3.1

6.8

MEDIUM

Description

A vulnerability was found in OpenSSH when the VerifyHostKeyDNS option is enabled. A machine-in-the-middle attack can be performed by a malicious machine impersonating a legit server. This issue occurs due to how OpenSSH mishandles error codes in specific conditions when verifying the host key. For an attack to be considered successful, the attacker needs to manage to exhaust the client's memory resource first, turning the attack complexity high.

Vendor	Product	Versions
Unknown	OpenSSH	affected `6.8p1 - <= 9.9p1`
Red Hat	Red Hat Enterprise Linux 8	unaffected `0:8.0p1-26.el8_10 - < *`
Red Hat	Red Hat Enterprise Linux 8	unaffected `0:8.0p1-26.el8_10 - < *`
Red Hat	Red Hat Enterprise Linux 9	unaffected `0:8.7p1-45.el9 - < *`
Red Hat	Red Hat Enterprise Linux 9	unaffected `0:8.7p1-45.el9 - < *`
Red Hat	Red Hat Enterprise Linux 9.4 Extended Update Support	unaffected `0:8.7p1-38.el9_4.5 - < *`
Red Hat	Red Hat Discovery 1.14	unaffected `sha256:f33991d766b618a128fb99fbe4f9b61c5004f7c6aa73b2b38e28d59e56c64d63 - < *`
Red Hat	Red Hat Enterprise Linux 10	All versions
Red Hat	Red Hat Enterprise Linux 6	All versions
Red Hat	Red Hat Enterprise Linux 7	All versions
Red Hat	Red Hat OpenShift Container Platform 4	All versions