Vulnerability Description
The GETALL and SETALL commands in semctl(2) recorded the number of semaphores in the target set, dropped the lock protecting the set, allocated a buffer sized for that count, and reacquired the lock. A sequence-number check was used to verify that the set had not been replaced in the interim, but the sequence number wraps after 0x8000 create/destroy cycles. By rapidly destroying and recreating semaphore sets at the same index, another process can cause the sequence number to wrap, allowing a set with a different number of semaphores to pass validation. The subsequent copy then reads or writes past the end of the allocated buffer. An unprivileged local user can trigger out-of-bounds reads and writes on kernel heap memory, potentially leading to privilege escalation.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Freebsd | Freebsd | 14.4 |
Related Weaknesses (CWE)
References
- https://security.freebsd.org/advisories/FreeBSD-SA-26:54.sysvsem.ascVendor AdvisoryMailing List
FAQ
What is CVE-2026-58087?
CVE-2026-58087 is a vulnerability with a CVSS score of 7.8 (HIGH). The GETALL and SETALL commands in semctl(2) recorded the number of semaphores in the target set, dropped the lock protecting the set, allocated a buffer sized for that count, and reacquired the lock. ...
How severe is CVE-2026-58087?
CVE-2026-58087 has been rated HIGH with a CVSS base score of 7.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-58087?
Check the references section above for vendor advisories and patch information. Affected products include: Freebsd Freebsd.