CVE-2024-6409
Openssh: possible remote code execution due to a race condition in signal handling affecting red hat enterprise linux 9
- Published
- Updated
- Reserved
- Assigned by
- redhat
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.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| redhatCNA (assigner) | 3.1 | High7.0 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H |
| NVDNVD · Deferred | 3.1 | High7.0 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H |
- EPSS (exploitation in 30 days)
- 27.9% · top 1.9% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.0.
Weakness
Affected products
OpenSSH
All versions: unaffected
Red Hat · Red Hat Enterprise Linux 9
- unaffected 0:8.7p1-38.el9_4.4 – < *
Red Hat · Red Hat Enterprise Linux 9
- unaffected 0:8.7p1-38.el9_4.4 – < *
Red Hat · Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions
- unaffected 0:8.7p1-12.el9_0.3 – < *
Red Hat · Red Hat Enterprise Linux 9.2 Extended Update Support
- unaffected 0:8.7p1-30.el9_2.7 – < *
Red Hat · Red Hat OpenShift Container Platform 4.13
- unaffected 413.92.202408122222-0 – < *
Red Hat · Red Hat OpenShift Container Platform 4.14
- unaffected 414.92.202407300859-0 – < *
Red Hat · Red Hat OpenShift Container Platform 4.15
- unaffected 415.92.202407301159-0 – < *
Red Hat · Red Hat OpenShift Container Platform 4.16
- unaffected 416.94.202407171205-0 – < *
Red Hat · Red Hat Enterprise Linux 10
All versions: unaffected
Red Hat · Red Hat Enterprise Linux 6
All versions: unaffected
Red Hat · Red Hat Enterprise Linux 7
All versions: unaffected
Red Hat · Red Hat Enterprise Linux 8
All versions: unaffected
What to do
Workaround: The process is identical to CVE-2024-6387, by disabling LoginGraceTime. See that CVE page for additional details.
References (24)
- RHSA-2024:4457 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
- RHSA-2024:4613 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
- RHSA-2024:4716 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
- RHSA-2024:4910 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2024:4955 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2024:4960 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2024:5444 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2024-6409 (opens in a new tab)vdb-entryx_refsource_REDHATx_transferred
- RHBZ#2295085 (opens in a new tab)issue-trackingx_refsource_REDHATx_transferred
- http://www.openwall.com/lists/oss-security/2024/07/08/2 (opens in a new tab)x_transferred
- http://www.openwall.com/lists/oss-security/2024/07/09/2 (opens in a new tab)x_transferred
- http://www.openwall.com/lists/oss-security/2024/07/09/5 (opens in a new tab)x_transferred
- http://www.openwall.com/lists/oss-security/2024/07/10/1 (opens in a new tab)x_transferred
- http://www.openwall.com/lists/oss-security/2024/07/10/2 (opens in a new tab)x_transferred
- https://almalinux.org/blog/2024-07-09-cve-2024-6409/ (opens in a new tab)x_transferred
- https://bugzilla.suse.com/show_bug.cgi?id=1227217 (opens in a new tab)x_transferred
- https://explore.alas.aws.amazon.com/CVE-2024-6409.html (opens in a new tab)x_transferred
- https://github.com/openela-main/openssh/commit/c00da7741d42029e49047dd89e266d91dcfbffa0 (opens in a new tab)x_transferred
- https://security-tracker.debian.org/tracker/CVE-2024-6409 (opens in a new tab)x_transferred
- https://security.netapp.com/advisory/ntap-20240712-0003/ (opens in a new tab)x_transferred
- https://sig-security.rocky.page/issues/CVE-2024-6409/ (opens in a new tab)x_transferred
- https://ubuntu.com/security/CVE-2024-6409 (opens in a new tab)x_transferred
- https://www.suse.com/security/cve/CVE-2024-6409.html (opens in a new tab)x_transferred
- https://cert-portal.siemens.com/productcert/html/ssa-398330.html (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2024-6409)Record last updated .