Skip to content
OpenAdvisories
High ALAS2023-2024-651 1 CVE

Important: openssh security update (Amazon Linux 2023)

Published Jul 18, 2024 · Updated Jul 22, 2024

Summary

Package updates are available for Amazon Linux 2023 that fix the following vulnerabilities: CVE-2024-6409: 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.

Fixed packages 11

ReleasePackageFixed in
Amazon Linux · 2023 openssh 0:8.7p1-8.amzn2023.0.12
Amazon Linux · 2023 openssh-clients 0:8.7p1-8.amzn2023.0.12
Amazon Linux · 2023 openssh-clients-debuginfo 0:8.7p1-8.amzn2023.0.12
Amazon Linux · 2023 openssh-debuginfo 0:8.7p1-8.amzn2023.0.12
Amazon Linux · 2023 openssh-debugsource 0:8.7p1-8.amzn2023.0.12
Amazon Linux · 2023 openssh-keycat 0:8.7p1-8.amzn2023.0.12
Amazon Linux · 2023 openssh-keycat-debuginfo 0:8.7p1-8.amzn2023.0.12
Amazon Linux · 2023 openssh-server 0:8.7p1-8.amzn2023.0.12
Amazon Linux · 2023 openssh-server-debuginfo 0:8.7p1-8.amzn2023.0.12
Amazon Linux · 2023 pam_ssh_agent_auth 0:0.10.4-4.8.amzn2023.0.12
Amazon Linux · 2023 pam_ssh_agent_auth-debuginfo 0:0.10.4-4.8.amzn2023.0.12

Vulnerabilities 1

  • High 7.0
    CVE-2024-6409 EPSS 28%

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

    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 …

References

  • web
    https://alas.aws.amazon.com/cve/html/CVE-2024-6409.html