MEDIUM

CVE-2025-26465

CVSS v3

6.8

MEDIUM

EPSS Score

7.7 %

exploit probability, as of 2026-10-19

CISA KEV

known exploited

Exploitation

—

SSVC status

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Affected and fixed versions

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

opensshAlmaLinux:9all versions · fixed in 8.7p1-45.el9and 4 other packages
opensshAlmaLinux:8all versions · fixed in 8.0p1-26.el8_10and 6 other packages
pam_ssh_agent_authAlmaLinux:9all versions · fixed in 0.10.4-5.45.el9
pam_ssh_agent_authAlmaLinux:8all versions · fixed in 0.10.3-7.26.el8_10

Vendor advisories

CVE-2025-26465 Red Hat Product Security285 products fixed · 18 known affected
openssh: Machine-in-the-middle attack if VerifyHostKeyDNS is enabled
openssh as a component of Red Hat Enterprise Linux 6 · openssh-askpass as a component of Red Hat Enterprise Linux 6 · openssh-clients as a component of Red Hat Enterprise Linux 6
ICSA-26-202-04 CISA1 known affected
Siemens SIDIS Secured SmartPlug
SIDIS Secured SmartPlug < V7.26.0310
SSA-585531 Siemens ProductCERT1 known affected
SSA-585531: Multiple Vulnerabilities in SIDIS Secured SmartPlug before V7.26.0310
SIDIS Secured SmartPlug < V7.26.0310
RHSA-2025:16823 Red Hat Product Security105 products fixed
Red Hat Security Advisory: openssh security update
ICSA-25-162-05 CISA5 known affected
Siemens SIMATIC S7-1500 CPU family
SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) · SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) · SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0)
SSA-082556 Siemens ProductCERT5 known affected
SSA-082556: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1.5
SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) >= V3.1.5 · SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) >= V3.1.5 · SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) >= V3.1.5

3 more advisories

Full record on NVD

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.

Technical details

Published: 2025-02-18

Frequently asked questions

What is CVE-2025-26465?

Is CVE-2025-26465 actively exploited?

Active exploitation of CVE-2025-26465 has not been confirmed. Its EPSS score was 7.7% on 2026-10-19, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2025-26465?

CVE-2025-26465 has a CVSS v3 base score of 6.8 (MEDIUM severity).

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