Public vulnerability disclosure
CVE-2024-6409
Openssh: possible remote code execution due to a race condition in signal handling affecting red hat enterprise linux 9
publishedCWE-364
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.
Technical severity7.0 highCVSS 3.1 · CNA: redhat
Published2024-07-08Source updated 2026-11-03
Collected2026-11-032 attributed sources
Fixes and workarounds
Workaround
The process is identical to CVE-2024-6387, by disabling LoginGraceTime. See that CVE page for additional details.
Source: CNA: redhatAffected products and versions
| Product | Versions | Authority |
|---|---|---|
OpenSSH
https://www.openssh.com/ |
Range not reported
Other versions: unaffected |
CNA: redhat |
| Red Hat Enterprise Linux 9 Red Hat openssh
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:8.7p1-38.el9_4.4; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions Red Hat openssh
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:8.7p1-12.el9_0.3; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 9.2 Extended Update Support Red Hat openssh
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:8.7p1-30.el9_2.7; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat OpenShift Container Platform 4.13 Red Hat openshift/ose-rhel-coreos-9
https://catalog.redhat.com/software/containers/ |
≥ 413.92.202408122222-0; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat OpenShift Container Platform 4.14 Red Hat openshift/ose-rhel-coreos-9
https://catalog.redhat.com/software/containers/ |
≥ 414.92.202407300859-0; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat OpenShift Container Platform 4.15 Red Hat openshift/ose-rhel-coreos-9
https://catalog.redhat.com/software/containers/ |
≥ 415.92.202407301159-0; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat OpenShift Container Platform 4.16 Red Hat openshift/ose-rhel-coreos-9
https://catalog.redhat.com/software/containers/ |
≥ 416.94.202407171205-0; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 10 Red Hat openssh
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: unaffected |
CNA: redhat |
| Red Hat Enterprise Linux 6 Red Hat openssh
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: unaffected |
CNA: redhat |
| Red Hat Enterprise Linux 7 Red Hat openssh
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: unaffected |
CNA: redhat |
| Red Hat Enterprise Linux 8 Red Hat openssh
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: unaffected |
CNA: redhat |
| SIMATIC S7-1500 CPU 1518-4 PN/DP MFP Siemens |
≥ V3.1.0; < V3.1.5 (affected, custom)
Other versions: unknown |
ADP: siemens-SADP |
| SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP Siemens |
≥ V3.1.0; < V3.1.5 (affected, custom)
Other versions: unknown |
ADP: siemens-SADP |
| SIPLUS S7-1500 CPU 1518-4 PN/DP MFP Siemens |
≥ V3.1.0; < V3.1.5 (affected, custom)
Other versions: unknown |
ADP: siemens-SADP |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 3.1 / 7.0 high |
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H | CNA: redhat |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://access.redhat.com/errata/RHSA-2024:4457CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2024:4613CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2024:4716CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2024:4910CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2024:4955CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2024:4960CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2024:5444CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2024-6409CNA: redhat · vdb-entry, x_refsource_REDHAT
- https://bugzilla.redhat.com/show_bug.cgi?id=2295085CNA: redhat · issue-tracking, x_refsource_REDHAT
- http://www.openwall.com/lists/oss-security/2024/07/08/2ADP: CVE · x_transferred
- http://www.openwall.com/lists/oss-security/2024/07/09/2ADP: CVE · x_transferred
- http://www.openwall.com/lists/oss-security/2024/07/09/5ADP: CVE · x_transferred
- http://www.openwall.com/lists/oss-security/2024/07/10/1ADP: CVE · x_transferred
- http://www.openwall.com/lists/oss-security/2024/07/10/2ADP: CVE · x_transferred
- https://access.redhat.com/errata/RHSA-2024:4457ADP: CVE · vendor-advisory, x_refsource_REDHAT, x_transferred
- https://access.redhat.com/errata/RHSA-2024:4613ADP: CVE · vendor-advisory, x_refsource_REDHAT, x_transferred
- https://access.redhat.com/errata/RHSA-2024:4716ADP: CVE · vendor-advisory, x_refsource_REDHAT, x_transferred
- https://access.redhat.com/security/cve/CVE-2024-6409ADP: CVE · vdb-entry, x_refsource_REDHAT, x_transferred
- https://almalinux.org/blog/2024-07-09-cve-2024-6409/ADP: CVE · x_transferred
- https://bugzilla.redhat.com/show_bug.cgi?id=2295085ADP: CVE · issue-tracking, x_refsource_REDHAT, x_transferred
- https://bugzilla.suse.com/show_bug.cgi?id=1227217ADP: CVE · x_transferred
- https://explore.alas.aws.amazon.com/CVE-2024-6409.htmlADP: CVE · x_transferred
- https://github.com/openela-main/openssh/commit/c00da7741d42029e49047dd89e266d91dcfbffa0ADP: CVE · x_transferred
- https://security-tracker.debian.org/tracker/CVE-2024-6409ADP: CVE · x_transferred
- https://security.netapp.com/advisory/ntap-20240712-0003/ADP: CVE · x_transferred
- https://sig-security.rocky.page/issues/CVE-2024-6409/ADP: CVE · x_transferred
- https://ubuntu.com/security/CVE-2024-6409ADP: CVE · x_transferred
- https://www.suse.com/security/cve/CVE-2024-6409.htmlADP: CVE · x_transferred
- https://cert-portal.siemens.com/productcert/html/ssa-398330.htmlADP: siemens-SADP
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