CVE-2026-39461

high
Published 2026-05-21 ยท Modified 2026-05-21
CVSS v3
8.8
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CVSS v4 NEW
โ€”
not yet in upstream
VIR risk
8.8

Description

libcasper(3) communicates with helper processes via UNIX domain sockets, and uses the select(2) system call to wait for data to become available. However, it does not verify that its socket descriptor fits within select(2)'s descriptor set size limit of FD_SETSIZE (1024). An attacker able to cause an application using libcasper(3) to allocate large file descriptors, e.g., by opening many descriptors and executing a program which is not careful to close them upon startup, may trigger stack corruption. If the target application runs with setuid root privileges, this could be used to escalate local privileges.

Predictions

Exploit likelihood
82%
Patch ETA
โ€”

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or โ€” if you've already worked around this in production โ€” publish your fix to the community-verified tier.

โœš Propose a mitigation on Community โ†’ Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

OS impact

freebsd FreeBSD Affected 3 releases
VersionStatusFixed in
15.0 Affected โ€”
14.4 Affected โ€”
14.3 Affected โ€”

References

CWEs

CWE-121

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.