CVE-2026-49412 (GCVE-0-2026-49412)

Vulnerability from cvelistv5 – Published: 2026-06-27 09:02 – Updated: 2026-06-27 09:02
VLAI
Title
Use-after-free bug in the IPV6_MSFILTER socket option handler
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.
Severity
No CVSS data available.
CWE
Assigner
References
Impacted products
Vendor Product Version
FreeBSD FreeBSD Affected: 15.0-RELEASE , < p10 (release)
Affected: 14.4-RELEASE , < p6 (release)
Affected: 14.3-RELEASE , < p15 (release)
Create a notification for this product.
Date Public
2026-06-09 23:30
Credits
Andrew Griffiths at Calif.io Maik Münch
Show details on NVD website
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        },
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      "descriptions": [
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        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-416",
              "description": "CWE-416: Use After Free",
              "lang": "en",
              "type": "CWE"
            }
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      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-27T09:02:55.482Z",
        "orgId": "63664ac6-956c-4cba-a5d0-f46076e16109",
        "shortName": "freebsd"
      },
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          "url": "https://security.freebsd.org/advisories/FreeBSD-SA-26:29.ip6_multicast.asc"
        }
      ],
      "title": "Use-after-free bug in the IPV6_MSFILTER socket option handler",
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    "dateReserved": "2026-05-29T20:24:28.615Z",
    "dateUpdated": "2026-06-27T09:02:55.482Z",
    "state": "PUBLISHED"
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  }
}


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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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