CVE-2026-49412 - Vulnerability Details - OpenCVE

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.

No CVSS v4.0

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation none

Automatable no

Technical Impact total

Vendors	Products
Freebsd	Freebsd

No data.

No data.

References

Link	Providers
https://security.freebsd.org/advisories/FreeBSD-SA-26:29.ip6_multicast.asc

History

Mon, 29 Jun 2026 13:30:00 +0000

Type	Values Removed	Values Added
Metrics		cvssV3_1 `{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}` ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

Sat, 27 Jun 2026 14:30:00 +0000

Type	Values Removed	Values Added
First Time appeared		Freebsd Freebsd freebsd
Vendors & Products		Freebsd Freebsd freebsd

Sat, 27 Jun 2026 09:15:00 +0000

Type	Values Removed	Values Added
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.
Title		Use-after-free bug in the IPV6_MSFILTER socket option handler
Weaknesses		CWE-416
References		https://security.freebsd.org/advisories/FreeBSD-SA-26:29.ip6_multicast.asc

MITRE

Status: PUBLISHED

Assigner: freebsd

Published: 2026-06-27T09:02:55.482Z

Updated: 2026-06-30T03:55:29.049Z

Reserved: 2026-05-29T20:24:28.615Z

Link: CVE-2026-49412

Vulnrichment

Updated: 2026-06-29T13:06:20.730Z

NVD

No data.

Redhat

No data.

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