{"id":"CVE-2026-64423","revision":"e7bc83b01437465a870b9ef79c8e53a9","records":[{"revision":"e7bc83b01437465a870b9ef79c8e53a9","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-64423","aliases":[],"title":"ipv4: igmp: remove multicast group from hash table on device destruction","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv4: igmp: remove multicast group from hash table on device destruction\n\nWhen a device is destroyed under RTNL, ip_mc_destroy_dev() iterates through\nthe multicast list and calls ip_ma_put() on each membership, scheduling\nthem for RCU reclamation. However, they are not unlinked from the device's\nmulticast hash table (mc_hash).\n\nSince the device remains published in dev->ip_ptr until after\nip_mc_destroy_dev() completes, concurrent RCU readers traversing mc_hash\ncan still locate and access the multicast group after its refcount is\ndecremented. If the RCU callback runs and frees the group while a reader is\naccessing it, a use-after-free occurs.\n\nFix this by unlinking the multicast group from mc_hash using\nip_mc_hash_remove() before scheduling it for reclamation.\n\nBUG: KASAN: slab-use-after-free in ip_check_mc_rcu+0x149/0x3f0\nRead of size 4 at addr ffff888009bf1408 by task mausezahn/2276\n\nCall Trace:\n \n dump_stack_lvl+0x67/0x90\n print_report+0x175/0x7c0\n kasan_report+0x147/0x180\n ip_check_mc_rcu+0x149/0x3f0\n udp_v4_early_demux+0x36d/0x12d0\n ip_rcv_finish_core+0xb8b/0x1390\n ip_rcv_finish+0x54/0x120\n NF_HOOK+0x213/0x2b0\n __netif_receive_skb+0x126/0x340\n process_backlog+0x4f2/0xf00\n __napi_poll+0x92/0x2c0\n net_rx_action+0x583/0xc60\n handle_softirqs+0x236/0x7f0\n do_softirq+0x57/0x80\n \n\nAllocated by task 2239:\n kasan_save_track+0x3e/0x80\n __kasan_kmalloc+0x72/0x90\n ____ip_mc_inc_group+0x31a/0xa40\n __ip_mc_join_group+0x334/0x3f0\n do_ip_setsockopt+0x16fa/0x2010\n ip_setsockopt+0x3f/0x90\n do_sock_setsockopt+0x1ad/0x300\n\nFreed by task 0:\n kasan_save_track+0x3e/0x80\n kasan_save_free_info+0x40/0x50\n __kasan_slab_free+0x3a/0x60\n __rcu_free_sheaf_prepare+0xd4/0x220\n rcu_free_sheaf+0x36/0x190\n rcu_core+0x8d9/0x12f0\n handle_softirqs+0x236/0x7f0","state":0,"publishedAt":"2026-07-25T08:51:01.485+00:00","modifiedAt":"2026-10-19T20:38:28.28+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n \"product\": \"Linux\",\n \"vendor\": \"Linux\",\n \"defaultStatus\": \"unaffected\",\n \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n \"programFiles\": [\n \"net/ipv4/igmp.c\"\n ],\n \"versions\": [\n {\n \"version\": \"e9897071350bd9d94a56b5b6f79c85b1a98fc7e7\",\n \"lessThan\": \"412ba7def06ffe974ba9a1d862b022362c54ffa5\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"e9897071350bd9d94a56b5b6f79c85b1a98fc7e7\",\n \"lessThan\": \"c6cb5f8ebe1c1a78710c19f102db9fe48b9e6ba9\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"e9897071350bd9d94a56b5b6f79c85b1a98fc7e7\",\n \"lessThan\": \"5f42729d74bd6c61306d864423290d92962de4e1\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"e9897071350bd9d94a56b5b6f79c85b1a98fc7e7\",\n \"lessThan\": \"76d030ac95e17f91d69a595f17ebc5979700cf9a\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"e9897071350bd9d94a56b5b6f79c85b1a98fc7e7\",\n \"lessThan\": \"8820b530cb2388503d7418228d03ba074bf7a03e\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"e9897071350bd9d94a56b5b6f79c85b1a98fc7e7\",\n \"lessThan\": \"2ca18df1c2611f70eb3eb487e02ae85eb703b284\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"e9897071350bd9d94a56b5b6f79c85b1a98fc7e7\",\n \"lessThan\": \"f91883031e5a62877a29ce139442973cbea769f1\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"e9897071350bd9d94a56b5b6f79c85b1a98fc7e7\",\n \"lessThan\": \"7993211bde166471dffac074dc965489f86531f8\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n }\n ]\n }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n \"product\": \"Linux\",\n \"vendor\": \"Linux\",\n \"defaultStatus\": \"affected\",\n \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n \"programFiles\": [\n \"net/ipv4/igmp.c\"\n ],\n \"versions\": [\n {\n \"version\": \"3.11\",\n \"status\": \"affected\"\n },\n {\n \"version\": \"0\",\n \"lessThan\": \"3.11\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"5.10.261\",\n \"lessThanOrEqual\": \"5.10.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"5.15.212\",\n \"lessThanOrEqual\": \"5.15.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.1.178\",\n \"lessThanOrEqual\": \"6.1.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.6.145\",\n \"lessThanOrEqual\": \"6.6.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.12.96\",\n \"lessThanOrEqual\": \"6.12.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.18.39\",\n \"lessThanOrEqual\": \"6.18.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"7.1.4\",\n \"lessThanOrEqual\": \"7.1.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"7.2\",\n \"lessThanOrEqual\": \"*\",\n \"status\": \"unaffected\",\n \"versionType\": \"original_commit_for_fix\"\n }\n ]\n }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/412ba7def06ffe974ba9a1d862b022362c54ffa5","https://git.kernel.org/stable/c/c6cb5f8ebe1c1a78710c19f102db9fe48b9e6ba9","https://git.kernel.org/stable/c/5f42729d74bd6c61306d864423290d92962de4e1","https://git.kernel.org/stable/c/76d030ac95e17f91d69a595f17ebc5979700cf9a","https://git.kernel.org/stable/c/8820b530cb2388503d7418228d03ba074bf7a03e","https://git.kernel.org/stable/c/2ca18df1c2611f70eb3eb487e02ae85eb703b284","https://git.kernel.org/stable/c/f91883031e5a62877a29ce139442973cbea769f1","https://git.kernel.org/stable/c/7993211bde166471dffac074dc965489f86531f8"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-64423","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-64423","identifiers":["CVE-2026-64423"]},"retained":false,"historicalAffected":[]}],"coverage":[]}