CVE-2025-26465Medium· 6.8▾ TwilightPoC availableA 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 …
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 37.4 · likelihood 1.5 · exploitation 12
A public proof-of-concept already exists for this vulnerability — see Exploit availability below.
Public exploit / PoC code seen in 1 source. Availability, not in-the-wild use.
Exploit-prediction probability, daily snapshots since Jul 14.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
Last analysed / modified upstream
7.0%
2 GitHub repos
7.0% → 7.7%
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.
openssh >= 6.9, <= 9.8openssh = 6.8openssh = 9.9active_iq_unified_managerontap = 9openshift_container_platform = 4.0debian_linux = 11.0debian_linux = 12.0enterprise_linux = 9.0Refer to the linked advisories for vendor-supplied fixes and affected version ranges.
Field changes observed since this record was first indexed.
Connected by shared product, vendor, weakness, or advisory.
CVE-2025-26466Medium· 5.9A flaw was found in the OpenSSH package
CVE-2024-6387High· 8.1A security regression (CVE-2006-5051) was discovered in OpenSSH's server (sshd)
CVE-2021-41617High· 7.0sshd in OpenSSH 6.2 through 8.x before 8.8, when certain non-default configurations are used, allows privilege escalation because supplemental groups are not initialized as expected
CVE-2023-51384Medium· 5.5In ssh-agent in OpenSSH before 9.6, certain destination constraints can be incompletely applied
CVE-2023-28531Critical· 9.8ssh-add in OpenSSH before 9.3 adds smartcard keys to ssh-agent without the intended per-hop destination constraints
CVE-2025-61984Low· 3.6ssh in OpenSSH before 10.1 allows control characters in usernames that originate from certain possibly untrusted sources, potentially leading to code execution when a ProxyCommand is used