{"id":"CVE-2026-74480","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-74480","summary":"net: bridge: stop fast-leave after deleting a port group","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->ports with pp = &p->next 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->ports 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.","published":"2026-08-15T12:27:13.803Z","modified":"2026-08-17T03:55:04.354246532Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"6.6.151"}],"fix":null,"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/4695430e8132420bf8de94da3eb36a6cf35fde6b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4c57056ca6aace2e9f94ae9298bf49ef6b0c95e4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a39789f211b8a4125f0c70e05b30cf715f4f187d"},{"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"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-17T03:55:04.354246532Z"}}