CVE-2024-6409 Openssh: possible remote code execution due to a race condition in signal handling affecting red hat enterprise linux 9
A race condition in OpenSSH's signal handling allows remote attackers to achieve code execution as an unprivileged user.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2024-6409?
CVE-2024-6409 is a high-severity vulnerability in Red Hat Enterprise Linux 10, published on 8 Jul 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-364
Which versions are affected by CVE-2024-6409?
Linux distribution packages (40)
openssh AlmaLinux:9 | All versions | 8.7p1-38.el9_4.4 |
openssh-askpass AlmaLinux:9 | All versions | 8.7p1-38.el9_4.4 |
openssh-clients AlmaLinux:9 | All versions | 8.7p1-38.el9_4.4 |
openssh-keycat AlmaLinux:9 | All versions | 8.7p1-38.el9_4.4 |
openssh-server AlmaLinux:9 | All versions | 8.7p1-38.el9_4.4 |
pam_ssh_agent_auth AlmaLinux:9 | All versions | 0.10.4-5.38.el9_4.4 |
openssh-askpass Red Hat:enterprise_linux:9::appstream | All versions | 0:8.7p1-38.el9_4.4 |
openssh-askpass-debuginfo Red Hat:enterprise_linux:9::appstream | All versions | 0:8.7p1-38.el9_4.4 |
openssh-clients-debuginfo Red Hat:enterprise_linux:9::appstream | All versions | 0:8.7p1-38.el9_4.4 |
openssh-debuginfo Red Hat:enterprise_linux:9::appstream | All versions | 0:8.7p1-38.el9_4.4 |
openssh-debugsource Red Hat:enterprise_linux:9::appstream | All versions | 0:8.7p1-38.el9_4.4 |
openssh-keycat-debuginfo Red Hat:enterprise_linux:9::appstream | All versions | 0:8.7p1-38.el9_4.4 |
openssh-server-debuginfo Red Hat:enterprise_linux:9::appstream | All versions | 0:8.7p1-38.el9_4.4 |
openssh-sk-dummy-debuginfo Red Hat:enterprise_linux:9::appstream | All versions | 0:8.7p1-38.el9_4.4 |
pam_ssh_agent_auth Red Hat:enterprise_linux:9::appstream | All versions | 0:0.10.4-5.38.el9_4.4 |
pam_ssh_agent_auth-debuginfo Red Hat:enterprise_linux:9::appstream | All versions | 0:0.10.4-5.38.el9_4.4 |
openssh Red Hat:enterprise_linux:9::baseos | All versions | 0:8.7p1-38.el9_4.4 |
openssh-askpass-debuginfo Red Hat:enterprise_linux:9::baseos | All versions | 0:8.7p1-38.el9_4.4 |
openssh-clients Red Hat:enterprise_linux:9::baseos | All versions | 0:8.7p1-38.el9_4.4 |
openssh-clients-debuginfo Red Hat:enterprise_linux:9::baseos | All versions | 0:8.7p1-38.el9_4.4 |
openssh-debuginfo Red Hat:enterprise_linux:9::baseos | All versions | 0:8.7p1-38.el9_4.4 |
openssh-debugsource Red Hat:enterprise_linux:9::baseos | All versions | 0:8.7p1-38.el9_4.4 |
openssh-keycat Red Hat:enterprise_linux:9::baseos | All versions | 0:8.7p1-38.el9_4.4 |
openssh-keycat-debuginfo Red Hat:enterprise_linux:9::baseos | All versions | 0:8.7p1-38.el9_4.4 |
openssh-server Red Hat:enterprise_linux:9::baseos | All versions | 0:8.7p1-38.el9_4.4 |
openssh-server-debuginfo Red Hat:enterprise_linux:9::baseos | All versions | 0:8.7p1-38.el9_4.4 |
openssh-sk-dummy-debuginfo Red Hat:enterprise_linux:9::baseos | All versions | 0:8.7p1-38.el9_4.4 |
pam_ssh_agent_auth-debuginfo Red Hat:enterprise_linux:9::baseos | All versions | 0:0.10.4-5.38.el9_4.4 |
openssh-askpass Red Hat:rhel_e4s:9.0::appstream | All versions | 0:8.7p1-12.el9_0.3 |
openssh-askpass-debuginfo Red Hat:rhel_e4s:9.0::appstream | All versions | 0:8.7p1-12.el9_0.3 |
openssh-clients-debuginfo Red Hat:rhel_e4s:9.0::appstream | All versions | 0:8.7p1-12.el9_0.3 |
openssh-debuginfo Red Hat:rhel_e4s:9.0::appstream | All versions | 0:8.7p1-12.el9_0.3 |
openssh-debugsource Red Hat:rhel_e4s:9.0::appstream | All versions | 0:8.7p1-12.el9_0.3 |
openssh-keycat-debuginfo Red Hat:rhel_e4s:9.0::appstream | All versions | 0:8.7p1-12.el9_0.3 |
openssh-server-debuginfo Red Hat:rhel_e4s:9.0::appstream | All versions | 0:8.7p1-12.el9_0.3 |
pam_ssh_agent_auth Red Hat:rhel_e4s:9.0::appstream | All versions | 0:0.10.4-4.12.el9_0.3 |
pam_ssh_agent_auth-debuginfo Red Hat:rhel_e4s:9.0::appstream | All versions | 0:0.10.4-4.12.el9_0.3 |
openssh Red Hat:rhel_e4s:9.0::baseos | All versions | 0:8.7p1-12.el9_0.3 |
openssh-askpass-debuginfo Red Hat:rhel_e4s:9.0::baseos | All versions | 0:8.7p1-12.el9_0.3 |
openssh-clients Red Hat:rhel_e4s:9.0::baseos | All versions | 0:8.7p1-12.el9_0.3 |
How do I fix CVE-2024-6409?
Apply the vendor's patch.
Is CVE-2024-6409 being exploited?
There is no known exploitation of CVE-2024-6409 in the wild and no public exploit code.
Sources
Also known as ALSA-2024:4457, CLSA-2024-1721929402, GHSA-79hg-h6r6-64mm, OESA-2024-1870, OESA-2024-1871, OESA-2024-1872 and 4 more.