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CVE PROGRAM SOURCE RECORD6.8 Medium

CVE-2025-26465

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

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Status
Published
Published
Updated
Assigning organization
redhat

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.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

OpenSSH

Default version status: unaffected

  • 6.8p1 to ≤ 9.9p1affected

Red Hat Red Hat Enterprise Linux 8

Default version status: affected

  • 0:8.0p1-26.el8_10 to < *unaffected

Red Hat Red Hat Enterprise Linux 8

Default version status: affected

  • 0:8.0p1-26.el8_10 to < *unaffected

Red Hat Red Hat Enterprise Linux 9

Default version status: affected

  • 0:8.7p1-45.el9 to < *unaffected

Red Hat Red Hat Enterprise Linux 9

Default version status: affected

  • 0:8.7p1-45.el9 to < *unaffected

Red Hat Red Hat Enterprise Linux 9.4 Extended Update Support

Default version status: affected

  • 0:8.7p1-38.el9_4.5 to < *unaffected

Red Hat Red Hat Discovery 1.14

Default version status: affected

  • 1.14.3-1748529279 to < *unaffected

Red Hat Red Hat Enterprise Linux 10

Default version status: unaffected

Red Hat Red Hat Enterprise Linux 6

Default version status: unknown

Red Hat Red Hat Enterprise Linux 7

Default version status: unknown

Red Hat Red Hat OpenShift Container Platform 4

Default version status: affected

References