Vulnerability Description
A file descriptor can be closed while a thread is blocked in a poll(2) or select(2) call waiting for that descriptor. Because the blocked thread does not hold a reference to the underlying object, this closure may result in the object being freed while the thread remains blocked. In this situation, the kernel must remove the blocked thread from the per-object wait queue prior to freeing the object. In the case of some file descriptor types, the kernel failed to unlink blocked threads from the object before freeing it. When the blocked thread is subsequently woken, it accesses memory that has already been freed resulting in a use-after-free vulnerability. The use-after-free vulnerability may be triggered by an unprivileged local user and can be exploited to obtain superuser privileges.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Freebsd | Freebsd | 14.3 |
Related Weaknesses (CWE)
References
FAQ
What is CVE-2026-45251?
CVE-2026-45251 is a vulnerability with a CVSS score of 7.8 (HIGH). A file descriptor can be closed while a thread is blocked in a poll(2) or select(2) call waiting for that descriptor. Because the blocked thread does not hold a reference to the underlying object, th...
How severe is CVE-2026-45251?
CVE-2026-45251 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-2026-45251?
Check the references section above for vendor advisories and patch information. Affected products include: Freebsd Freebsd.