Use After Free in FreeBSD

CVE-2026-58090

The SOCK_STREAM receive path in the unix socket implementation failed to fully detach control messages from the socket buffer before processing them. Some error paths would free those messages, leaving freed data mbufs in the receive socket buffer. An unprivileged local user can exploit this use-after-free to escalate privileges.

Vulnerability class: Use-After-Free

EPSS: 0.002 (5.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-58090?
CVE-2026-58090 is a high-severity vulnerability in FreeBSD, classified under Use After Free. CVSS score: 7.8/10. Published 2026-08-26.
How severe is CVE-2026-58090?
High severity. CVSS v3 base score is 7.8 out of 10.