CVE-2026-49412
Published:June 27, 2026
Updated:June 29, 2026
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.
Affected Packages
https://github.com/freebsd/freebsd-src.git (GITHUB):
Affected version(s) >=release/14.4.0 <release/14.4.0-p6Fix Suggestion:
Update to version release/14.4.0-p6https://github.com/freebsd/freebsd-src.git (GITHUB):
Affected version(s) >=release/14.3.0 <release/14.3.0-p15Fix Suggestion:
Update to version release/14.3.0-p15https://github.com/freebsd/freebsd-src.git (GITHUB):
Affected version(s) >=release/15.0.0 <release/15.0.0-p10Fix Suggestion:
Update to version release/15.0.0-p10Related Resources (1)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.5
Attack Vector
LOCAL
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
LOW
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.8
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Weakness Type (CWE)
Use After Free
EPSS
Base Score:
0.13