PatchTheCVECVE-2026-45251: A file descriptor can be closed while a thread is blocked in a poll(2) or select(2) call waiting for that desc
CVE-2026-45251 is a high-severity flaw (CVSS 7.8) affecting freebsd. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
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, th
Why this priority
- High severity
No fix is published yet: follow the downgrade or mitigation steps.
Risk facts
| CVSS score | 7.8 (High) |
| Attack vector | Local |
| Attack complexity | Low |
| Privileges needed | Low |
| User interaction | None |
| EPSS exploit chance | 0.2% (top 94%) |
| CISA exploited list | No |
| Weakness | CWE-416 |
| Published | 2026-05-21 |
| Last modified | 2026-07-23 |
Last updated 2026-07-23 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-45251?
freebsd: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.
Is CVE-2026-45251 being exploited?
CVE-2026-45251 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-45251 affect?
CVE-2026-45251 affects freebsd. Severity is high (CVSS 7.8). 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 bein
How urgent is CVE-2026-45251?
Priority 29/100. High severity
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