CVE-2024-6409 HIGH

CVE-2024-6409: Openssh: possible remote code execution due to a race condition in signal handling affecting red hat enterprise linux 9

Vendor Red Hat
Product Red Hat Enterprise Linux 10
Weakness CWE-364
Published July 8, 2024
Last update November 11, 2025

CVSS base score

7.0/10
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Confidentiality Low
Integrity Low

CVSS vector

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

What the vulnerability does

01Description

A race condition vulnerability was discovered in how signals are handled by OpenSSH's server (sshd). If a remote attacker does not authenticate within a set time period, then sshd's SIGALRM handler is called asynchronously. However, this signal handler calls various functions that are not async-signal-safe, for example, syslog(). As a consequence of a successful attack, in the worst case scenario, an attacker may be able to perform a remote code execution (RCE) as an unprivileged user running the sshd server.

Key dates

02Disclosure timeline

July 8, 2024 CVE published
November 11, 2025 Record updated