Quick answers
- Is CVE-2026-58092 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-58092 being exploited in the wild.
- How severe is CVE-2026-58092?
- High severity, with a CVSS score of 8.1, published 26 August 2026.
- Which products and versions are affected?
- Freebsd 15.0.
- Is there a fix for CVE-2026-58092?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-58092 attacked?
- It is attacked with local access, in an operating system.
- Am I affected by CVE-2026-58092?
- Check whether you run Freebsd at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A logic error in the group_is_primary() function within FreeBSD 15.0's kernel credential subsystem causes it to read the primary group ID from the wrong location after a credential structure refactoring. When mac_do applies a transition rule (such as "uid=1001>uid=1002") that does not explicitly specify a target group, the function incorrectly retrieves the group ID from the first element of the supplementary group array instead of the dedicated primary group ID field. An attacker with a matching source UID can exploit this to set their primary group ID to 0 (wheel) if they have first removed themselves from all supplementary groups via setgroups(2). Depending on system configuration, membership in group 0 may grant root-equivalent privileges, enabling full privilege escalation. The vulnerability requires a matching mac_do rule and local system access.
Affected products
- FreeBSD FreeBSD 15.0
Timeline
- 2026-08-26: disclosed