Improper privilege management in FreeBSD - CVE-2026-58092
Published: August 26, 2026
Vulnerability identifier: #VU145747
CSH Severity: Low
CVSS v4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-58092
CWE-ID: CWE-269
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 improper handling of primary group identification in group_is_primary() in the mac_do policy module when applying credential transition rules that do not explicitly specify a target group. A local user can trigger a crafted credential switch to set an unintended primary group ID to escalate privileges.
Exploitation requires a mac_do ruleset that applies to the calling process, and setting the primary group ID to 0 requires the process to have an empty supplementary group list.
Affected software
FreeBSD
How to mitigate CVE-2026-58092
Install security update from vendor's website.