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Untriaged
Permalink CVE-2025-26465
6.8 MEDIUM
  • CVSS version: 3.1
  • Attack vector (AV): NETWORK
  • Attack complexity (AC): HIGH
  • Privileges required (PR): NONE
  • User interaction (UI): REQUIRED
  • Scope (S): UNCHANGED
  • Confidentiality impact (C): HIGH
  • Integrity impact (I): HIGH
  • Availability impact (A): NONE
created 6 months, 1 week ago
Openssh: machine-in-the-middle attack if verifyhostkeydns is enabled

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.

References

Affected products

rhcos
OpenSSH
  • =<9.9p1
openssh
  • *
discovery/discovery-server-rhel9
  • *
registry.redhat.io/discovery/discovery-server-rhel9
  • *

Matching in nixpkgs

pkgs.openssh

Implementation of the SSH protocol

  • nixos-unstable -

pkgs.openssh_hpn

Implementation of the SSH protocol with high performance networking patches

  • nixos-unstable -

pkgs.openssh_gssapi

Implementation of the SSH protocol with GSSAPI support

  • nixos-unstable -

Package maintainers