Improper access control in FreeBSD - CVE-2026-45259
Published: June 11, 2026
Vulnerability identifier: #VU134366
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-45259
CWE-ID: CWE-284
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: FreeBSD Foundation
Affected software:
FreeBSD
FreeBSD
Detailed vulnerability description
The vulnerability allows a local user to interfere with other processes.
The vulnerability exists due to improper access control in kern_sigqueue when sending signals via sigqueue(2) from a process in capability mode. A local user can send signals to processes other than the calling process to interfere with other processes.
This issue allows bypass of Capsicum sandbox restrictions and may affect processes running as the same user, or any process if the sandboxed process runs with superuser privileges.
How to mitigate CVE-2026-45259
Install security update from vendor's website.