SSH: OpenSSH sshd SSH2_MSG_PING Denial Of Service

This signature detects attempts to exploit a known vulnerability against OpenSSH sshd SSH2_MSG_PING. A successful attack can result in a denial-of-service condition.

Extended Description

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.

Affected Products

Openbsd openssh

References

CVE: CVE-2025-26466

Short Name

SSH:OPENSSH:PING-DOS

Severity

Major

Recommended

False

Recommended Action

Drop

SSH: OpenSSH sshd SSH2_MSG_PING Denial Of Service

Extended Description

Affected Products

References

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