CVE-2026-49412

HIGH

Use-after-free bug in the IPV6_MSFILTER socket option handler

Title source: cna
STIX 2.1

Description

The kernel handler for IPV6_MSFILTER dropped a serializing lock in order to copy the source-filter list from userspace, then reacquired the lock. During this window another thread could free the multicast filter structure, leaving the handler with a stale pointer to freed memory. An unprivileged local user can exploit this use-after-free to escalate privileges.

References (1)

Core 1
Core References

Scores

CVSS v3 7.8
EPSS 0.0010
EPSS Percentile 1.3%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact total

Details

CWE
CWE-416
Status published
Products (6)
freebsd/freebsd 14.3 (15 CPE variants)
freebsd/freebsd 14.4 (6 CPE variants)
freebsd/freebsd 15.0 (10 CPE variants)
FreeBSD/FreeBSD 14.3-RELEASE - p15
FreeBSD/FreeBSD 14.4-RELEASE - p6
FreeBSD/FreeBSD 15.0-RELEASE - p10
Published Jun 27, 2026
Tracked Since Jun 27, 2026