{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "6db6f0eae6052b70885562e1733896647ec1d807"
            },
            {
              "fixed": "d6c32e2e25a9a06ba021030e26b6d602a277eb72"
            },
            {
              "fixed": "482bcb85139addb4e8ac8ed10baeda3e0aad4031"
            },
            {
              "fixed": "1a109cc9890d017c41d77e6c82da739579c49f0b"
            },
            {
              "fixed": "159ad90cb929c033308bb39a2c5f8fbf393b77aa"
            },
            {
              "fixed": "4695430e8132420bf8de94da3eb36a6cf35fde6b"
            },
            {
              "fixed": "0309ebbc570000ea0df11c06b69798e5860c5f6f"
            },
            {
              "fixed": "4c57056ca6aace2e9f94ae9298bf49ef6b0c95e4"
            },
            {
              "fixed": "a39789f211b8a4125f0c70e05b30cf715f4f187d"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.11.0"
            },
            {
              "fixed": "5.10.265"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.216"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.183"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.151"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.103"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.44"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.1.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74480.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: bridge: stop fast-leave after deleting a port group\n\nbr_multicast_leave_group() iterates mp-\u003eports with pp = \u0026p-\u003enext in\nits fast-leave path. After br_multicast_del_pg() removes p,\ncontinuing the loop advances pp through the deleted entry.\n\nIf multicast-to-unicast was enabled, the bridge can hold multiple port\ngroups for the same port and group with different source MAC\naddresses. Once multicast-to-unicast is disabled,\nbr_port_group_equal() matches those entries by port only. A fast leave\ncan then delete one entry and continue from its stale next pointer,\nleaving mp-\u003eports pointing at a deleted port group.\n\nFast leave only needs to remove one matching port group. Break after\nbr_multicast_del_pg() so the loop stops before dereferencing the\nremoved entry.",
  "id": "CVE-2026-74480",
  "modified": "2026-08-21T03:30:24.764144797Z",
  "published": "2026-08-15T12:27:13.803Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0309ebbc570000ea0df11c06b69798e5860c5f6f"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/159ad90cb929c033308bb39a2c5f8fbf393b77aa"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1a109cc9890d017c41d77e6c82da739579c49f0b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4695430e8132420bf8de94da3eb36a6cf35fde6b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/482bcb85139addb4e8ac8ed10baeda3e0aad4031"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4c57056ca6aace2e9f94ae9298bf49ef6b0c95e4"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a39789f211b8a4125f0c70e05b30cf715f4f187d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d6c32e2e25a9a06ba021030e26b6d602a277eb72"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74480.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-74480"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "net: bridge: stop fast-leave after deleting a port group"
}