CVE-2026-58098 (GCVE-0-2026-58098)
Vulnerability from cvelistv5 – Published: 2026-10-15 06:15 – Updated: 2026-10-16 14:16
VLAI
EPSS
VEX
Title
Heap out-of-bounds access in semop(2)
Summary
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.
Severity
8.4 (High)
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-16 03:56 UTC
CWE
- CWE-787 - Out-of-bounds Write
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://security.freebsd.org/advisories/FreeBSD-S… | vendor-advisory |
Impacted products
Date Public
2026-09-29 20:30
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