CVE-2025-26466 MEDIUM

CVE-2025-26466: Openssh: denial-of-service in openssh

Vendor Red Hat
Product Red Hat Enterprise Linux 10
Weakness CWE-770 · Uncontrolled resource consumption
Published February 28, 2025
Last update February 10, 2026

CVSS base score

5.9/10
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Confidentiality None
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

What the vulnerability does

01Description

A flaw was found in the OpenSSH package. For each ping packet the SSH server receives, a pong packet is allocated in a memory buffer and stored in a queue of packages. It is only freed when the server/client key exchange has finished. A malicious client may keep sending such packages, leading to an uncontrolled increase in memory consumption on the server side. Consequently, the server may become unavailable, resulting in a denial of service attack.

Key dates

02Disclosure timeline

February 28, 2025 CVE published
February 10, 2026 Record updated