CVE-2026-49412

HIGHCVSS 7.8/10EPSS 0.10%

Last modified

CVE-2026-49412 is a high-severity vulnerability rated 7.8/10 on the CVSS scale. 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.. EPSS estimates a 0.10% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1
7.8/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Probability
0.10%

1.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

VendorProductVersions
FreebsdFreebsd14.3
FreebsdFreebsd14.4
FreebsdFreebsd15.0

References

Timeline

Published
Last Modified
Status
Analyzed

Frequently Asked Questions

What is CVE-2026-49412?
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.
How severe is CVE-2026-49412?
CVE-2026-49412 has a CVSS score of 7.8/10 (HIGH severity). The EPSS model estimates a 0.10% probability of exploitation in the next 30 days.
How do I fix CVE-2026-49412?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

How Strix Helps

Related CVEs from 2026

Are you affected by CVE-2026-49412?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST