Out-of-bounds read in FreeBSD - CVE-2026-58100
Published: September 30, 2026
Vulnerability identifier: #VU152950
CSH Severity: Low
CVSS v4: 7.3 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-58100
CWE-ID: CWE-125
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to escalate privileges.
The vulnerability exists due to an out-of-bounds read in kqueue_fork_copy_knote() when transferring knotes to a child process during fork. A local user can concurrently grow the parent's file descriptor table and register knotes with file descriptor numbers beyond the child table's bounds to escalate privileges.
Affected software
FreeBSD
How to mitigate CVE-2026-58100
Install security update from vendor's website.