Vulnerability 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.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Openbsd | Openssh | >= 6.9, <= 9.8 |
| Netapp | Active Iq Unified Manager | - |
| Netapp | Ontap | 9 |
| Redhat | Openshift Container Platform | 4.0 |
| Debian | Debian Linux | 11.0 |
| Redhat | Enterprise Linux | 9.0 |
Related Weaknesses (CWE)
References
- https://access.redhat.com/errata/RHSA-2025:16823
- https://access.redhat.com/errata/RHSA-2025:3837
- https://access.redhat.com/errata/RHSA-2025:6993
- https://access.redhat.com/errata/RHSA-2025:8385
- https://access.redhat.com/security/cve/CVE-2025-26465Third Party Advisory
- https://access.redhat.com/solutions/7109879
- https://bugzilla.redhat.com/show_bug.cgi?id=2344780Issue TrackingThird Party Advisory
- https://seclists.org/oss-sec/2025/q1/144Mailing ListThird Party Advisory
- http://seclists.org/fulldisclosure/2025/Feb/18
- http://seclists.org/fulldisclosure/2025/May/7
- http://seclists.org/fulldisclosure/2025/May/8
- https://blog.qualys.com/vulnerabilities-threat-research/2025/02/18/qualys-tru-diThird Party Advisory
- https://bugzilla.suse.com/show_bug.cgi?id=1237040Issue Tracking
- https://ftp.openbsd.org/pub/OpenBSD/patches/7.6/common/008_ssh.patch.sigPatch
- https://lists.debian.org/debian-lts-announce/2025/02/msg00020.htmlThird Party Advisory
FAQ
What is CVE-2025-26465?
CVE-2025-26465 is a vulnerability with a CVSS score of 6.8 (MEDIUM). 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...
How severe is CVE-2025-26465?
CVE-2025-26465 has been rated MEDIUM with a CVSS base score of 6.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2025-26465?
Check the references section above for vendor advisories and patch information. Affected products include: Openbsd Openssh, Netapp Active Iq Unified Manager, Netapp Ontap, Redhat Openshift Container Platform, Debian Debian Linux.