CVE-2025-26465
CWE-390Published: February 18, 2025· Updated: Jul 14, 2026
Official 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.
Technical Analysis
CVE-2025-26465 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
Exploitation does not require any privileges, though user interaction (Required) is needed, which slightly reduces the risk of mass automated attacks.
A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), with a CVSS base score of 6.8.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (28)
Quick Facts
Related CVEs (CWE-390)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2025-26465 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts