CVE-2026-58099Memory safety bugs in kqueue copy-on-fork implementation
Updated under an hour ago ()
Does this affect you?
It affects FreeBSD. Add what you run to find out whether that includes you.
EPSS puts the chance of exploitation in the next 30 days at 0.10%, higher than 1% of scored CVEs.
Do this next
Free account, 1 product
When copying knotes from a parent kqueue to a child, the copy code did not correctly exclude marker knotes (used internally to track list traversal position) before marking them as in-flux and releasing the kqueue lock. If another thread freed a marker while the lock was dropped, the subsequent in-flux decrement operated on freed memory. An unprivileged local user may be able to exploit these races to escalate privileges.
- CVSS
- 7.0 HIGH (v3.1, CISA ADP)CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- Weakness (CWE)
- CWE-362, CWE-416
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- 0.10% (percentile 1)
- Assigned by
- freebsd
- NVD analysis
- Analyzed
- Record last updated
- Oct 19, 2026
- First seen by InfoSec Signals
- Oct 15, 2026
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.