Qualys TRU Discovers Two Vulnerabilities in OpenSSH: CVE-2025-26465 & CVE-2025-26466 | Qualys Security Blog
blog.qualys.com
The Qualys Threat Research Unit (TRU) has identified two vulnerabilities in OpenSSH. The first, tracked as CVE-2025-26465, allows an active machine-in-the-middle attack on the OpenSSH client when the…

cross-posted from: https://lemmy.ml/post/26304038

from the OpenSSH 9.9p2 release announcement:


This release fixes two security bugs.

Security
========

* Fix CVE-2025-26465 - ssh(1) in OpenSSH versions 6.8p1 to 9.9p1
  (inclusive) contained a logic error that allowed an on-path
  attacker (a.k.a MITM) to impersonate any server when the
  VerifyHostKeyDNS option is enabled. This option is off by default.

* Fix CVE-2025-26466 - sshd(8) in OpenSSH versions 9.5p1 to 9.9p1
  (inclusive) is vulnerable to a memory/CPU denial-of-service related
  to the handling of SSH2_MSG_PING packets. This condition may be
  mitigated using the existing PerSourcePenalties feature.

Both vulnerabilities were discovered and demonstrated to be exploitable
by the Qualys Security Advisory team. We thank them for their detailed
review of OpenSSH.