Riskcovery

CVE-2025-26465

Openssh: machine-in-the-middle attack if verifyhostkeydns is enabled

State
Published
Severity
6.8 Medium
Published
Feb 18, 2025
Updated
Oct 21, 2026
Reserved
Feb 10, 2025

Read the record on cve.org

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.

Scores

CVSSScoreVectorSource
3.16.8 MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:Nredhat

Weaknesses

  • CWE-390 Detection of Error Condition Without Action

Affected Products

ProductVersions
OpenSSH
  • 6.8p1 through 9.9p1Affected
Red Hat Enterprise Linux 8Red Hat
  • 0:8.0p1-26.el8_10 and laterNot affected
Red Hat Enterprise Linux 8Red Hat
  • 0:8.0p1-26.el8_10 and laterNot affected
Red Hat Enterprise Linux 9Red Hat
  • 0:8.7p1-45.el9 and laterNot affected
Red Hat Enterprise Linux 9Red Hat
  • 0:8.7p1-45.el9 and laterNot affected
Red Hat Enterprise Linux 9.4 Extended Update SupportRed Hat
  • 0:8.7p1-38.el9_4.5 and laterNot affected
Red Hat Discovery 1.14Red Hat
  • 1.14.3-1748529279 and laterNot affected
Red Hat Enterprise Linux 10Red Hat
    Red Hat Enterprise Linux 6Red Hat
      Red Hat Enterprise Linux 7Red Hat
        Red Hat OpenShift Container Platform 4Red Hat

          References

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