CVE-2026-58098

Published Oct 15, 2026

Last updated a day ago

Overview

Description
When semop(2) blocks waiting for a semaphore condition, it releases the per-set lock and sleeps. Upon waking, it checks the sequence number embedded in the semaphore set's IPC identifier to detect whether the set was removed while the caller was asleep. This sequence number is only 15 bits wide. If enough semaphore sets are created and destroyed in the same table slot while a caller is blocked, the counter wraps around, and semop(2) may falsely conclude that the original set still exists. The subsequent access to a semaphore within the set may then be out of bounds. An unprivileged local user can trigger an out-of-bounds access on kernel heap memory, potentially leading to privilege escalation.
Source
secteam@freebsd.org
NVD status
Analyzed
Products
freebsd

Risk scores

CVSS 3.1

Type
Secondary
Base score
8.4
Impact score
5.9
Exploitability score
2.5
Vector string
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

Weaknesses

secteam@freebsd.org
CWE-787

Social media

Hype score
Not currently trending

Configurations

References

Sources include official advisories and independent security research.