CVE-2026-49412

Summary

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 Software

VendorProductVersion RangeStatus
FreeBSDFreeBSD15.0-RELEASE < p10affected
FreeBSDFreeBSD14.4-RELEASE < p6affected
FreeBSDFreeBSD14.3-RELEASE < p15affected

Weaknesses

  • CWE-416: CWE-416: Use After Free

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: total

References