Vulnerability in FreeBSD
CVE-2024-7589
A signal handler in sshd(8) may call a logging function that is not async-signal-safe. The signal handler is invoked when a client does not authenticate within the LoginGraceTime seconds (120 by default). This signal handler executes in the context of the sshd(8)'s privileged code, which is not sandboxed and runs with full root privileges. This issue is another instance of the problem in CVE-2024-6387 addressed by FreeBSD-SA-24:04.openssh. The faulty code in this case is from the integration of blacklistd in OpenSSH in FreeBSD. As a result of calling functions that are not async-signal-safe in the privileged sshd(8) context, a race condition exists that a determined attacker may be able to exploit to allow an unauthenticated remote code execution as root.
Vulnerability class: Race Condition
EPSS: 0.020 (79.1th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Freebsd — versions 13.3, 14.0, 14.0-RELEASE
Weakness classification (CWE)
Public proof-of-concept exploits
References
- secteam@freebsd.org (vendor-advisory, Vendor Advisory)
- secteam@freebsd.org (related, Not Applicable)
- secteam@freebsd.org (related, Third Party Advisory)
- af854a3a-2127-422b-91ae-364da2661108
Frequently asked questions
- What is CVE-2024-7589?
- CVE-2024-7589 is a high-severity vulnerability in FreeBSD, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 8.1/10. Published 2024-08-12.
- How severe is CVE-2024-7589?
- High severity. CVSS v3 base score is 8.1 out of 10.
- Is CVE-2024-7589 known to be exploited?
- 3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.