{"id":"CVE-2026-58099","aliases":["EUVD-2026-101856","GHSA-f53j-rp59-76p7"],"status":"published","title":"Memory safety bugs in kqueue copy-on-fork implementation","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.\n\nAn unprivileged local user may be able to exploit these races to escalate privileges.","severity":{"version":"3.1","score":7,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"adp","from":"cve"},"epss":{"day":"2026-11-10","score":0.001,"percentile":0.00844,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-362","CWE-416"],"published":"2026-10-15T06:31:18Z","modified":"2026-10-19T21:02:15Z","products":[{"vendor":"freebsd","product":"freebsd"}],"references":[{"url":"https://security.freebsd.org/advisories/FreeBSD-SA-26:65.kqueue.asc","tags":["vendor-advisory","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-58099"},{"url":"https://github.com/advisories/GHSA-f53j-rp59-76p7"}],"sources":{"cve":[{"id":"CVE-2026-58099","title":"Memory safety bugs in kqueue copy-on-fork implementation","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.\n\nAn unprivileged local user may be able to exploit these races to escalate privileges.","status":"published","published":"2026-10-15T06:31:18.042Z","modified":"2026-10-19T14:10:47.179Z","cvss":[{"version":"3.1","score":7,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"adp"}],"cwes":["CWE-362","CWE-416"],"updated_at":"2026-11-02T13:47:28.691429Z"}],"euvd":[{"id":"EUVD-2026-101856","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.\n\nAn unprivileged local user may be able to exploit these races to escalate privileges.","status":"published","published":"2026-10-15T06:31:18Z","modified":"2026-10-19T14:10:47Z","cvss":[{"version":"3.1","score":7,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T16:59:51.186399Z"}],"ghsa":[{"id":"GHSA-f53j-rp59-76p7","title":"When copying knotes from a parent kqueue to a child, the copy code did not correctly exclude...","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.\n\nAn unprivileged local user may be able to exploit these races to escalate privileges.","status":"published","published":"2026-10-15T09:30:33Z","modified":"2026-10-19T15:32:29Z","cvss":[{"version":"3.1","score":7,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-362"],"updated_at":"2026-11-02T15:13:57.032902Z"}],"nvd":[{"id":"CVE-2026-58099","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.\n\nAn unprivileged local user may be able to exploit these races to escalate privileges.","status":"published","published":"2026-10-15T07:18:02.373Z","modified":"2026-10-19T21:02:15.75Z","cvss":[{"version":"3.1","score":7,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-362","CWE-416"],"updated_at":"2026-11-02T14:12:59.328869Z"}]}}