CVE-2026-58099
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.10%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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 3.1
- 7.0 HIGHCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.10% probability · 1th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-362, CWE-416
- Affected
- freebsd/freebsd
- Source
- secteam@freebsd.org
EPSS moved from 0.1% on 15 October 2026 to 0.1% on 26 October 2026.
References
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.