CVE-2025-26465
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.
- Affected products
- Alt Linux, Almalinux, Astra Linux, Centos, Freebsd, Ibm Aix, Linuxmint, Apple Macos
- Openbsd Openssh
- ≤ 9.8, 6.8, 9.9
- Fix
- Available
- CVSS 3.1
- 6.8 MEDIUM
- EPSS
- 7.6% (94th percentile)
- Weakness
- CWE-390
- NVD status
- Modified
- Published
- 2025-02-18
Workaround
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
CVE-2025-26465 at NVD
9 known exploits for CVE-2025-26465
Proof-of-concept code and exploit modules indexed by Sploitus
CVE-2025-26465
patch-manual-CVE-2025-26465-e-CVE-2025-26466
CVE-2025-26466-msf
Exploit for Allocation of Resources Without Limits or Throttling in Openbsd Openssh
📄 Apple Security Advisory 05-12-2025-4
📄 Apple Security Advisory 05-12-2025-3
OpenSSH 9.9p1 Denial of Service / Man-In-The-Middle Vulnerability
OpenSSH 9.9p1 Denial of Service / Man-In-The-Middle
Exploit for Detection of Error Condition Without Action in Openbsd Openssh