CVE-2024-6409

Public on 2024-07-08
Modified on 2024-07-08
Description
A signal handler race condition vulnerability was found in OpenSSH's server (sshd), where a client does not authenticate within LoginGraceTime seconds (120 by default, 600 in old OpenSSH versions), then sshd's SIGALRM handler is called asynchronously. However, this signal handler calls various functions that are not async-signal-safe, for example, syslog(). This issue leaves it vulnerable to a signal handler race condition on the cleanup_exit() function, which introduces the same vulnerability as CVE-2024-6387 in the unprivileged child of the SSHD server.
Severity
Important severity
Important
CVSS v3 Base Score
7.0
See breakdown

Affected Packages

Platform Package Release Date Advisory Status
Amazon Linux 1 openssh Not Affected
Amazon Linux 2 - Core openssh Not Affected
Amazon Linux 2023 openssh 2024-07-18 ALAS2023-2024-651 Fixed

CVSS Scores

Score Type Score Vector
Amazon Linux CVSSv3 7.0 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H
NVD CVSSv3 7.0 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H