Stack-based buffer overflow in FreeBSD - CVE-2026-45250
Published: May 21, 2026
Vulnerability identifier: #VU132006
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-45250
CWE-ID: CWE-121
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 execute arbitrary code.
The vulnerability exists due to stack-based buffer overflow in the setcred(2) system call when copying a user-supplied supplementary groups list into a fixed-size kernel stack buffer. A local user can supply an oversized supplementary groups list to execute arbitrary code.
The issue can be triggered before the caller's privilege level is checked, and successful exploitation occurs in the context of the kernel.
How to mitigate CVE-2026-45250
Install security update from vendor's website.