{"id":"CVE-2026-53275","summary":"ipv6: mcast: Fix use-after-free when processing MLD queries","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: mcast: Fix use-after-free when processing MLD queries\n\nWhen processing an MLD query, a pointer to the multicast group address\nis retrieved when initially parsing the packet. This pointer is later\ndereferenced without being reloaded despite the fact that the skb header\nmight have been reallocated following the pskb_may_pull() calls, leading\nto a use-after-free [1].\n\nFix by copying the multicast group address when the packet is initially\nparsed.\n\n[1]\nBUG: KASAN: slab-use-after-free in __mld_query_work (net/ipv6/mcast.c:1512)\nRead of size 8 at addr ffff8881154b8e90 by task kworker/4:1/118\n\nWorkqueue: mld mld_query_work\nCall Trace:\n\u003cTASK\u003e\ndump_stack_lvl (lib/dump_stack.c:94 lib/dump_stack.c:120)\nprint_address_description.constprop.0 (mm/kasan/report.c:378)\nprint_report (mm/kasan/report.c:482)\nkasan_report (mm/kasan/report.c:595)\n__mld_query_work (net/ipv6/mcast.c:1512)\nmld_query_work (net/ipv6/mcast.c:1563)\nprocess_one_work (kernel/workqueue.c:3314)\nworker_thread (kernel/workqueue.c:3397 kernel/workqueue.c:3478)\nkthread (kernel/kthread.c:436)\nret_from_fork (arch/x86/kernel/process.c:158)\nret_from_fork_asm (arch/x86/entry/entry_64.S:245)\n\u003c/TASK\u003e\n\n[...]\n\nFreed by task 118:\nkasan_save_stack (mm/kasan/common.c:57)\nkasan_save_track (mm/kasan/common.c:78)\nkasan_save_free_info (mm/kasan/generic.c:584)\n__kasan_slab_free (mm/kasan/common.c:253 mm/kasan/common.c:285)\nkfree (./include/linux/kasan.h:235 mm/slub.c:2689 mm/slub.c:6251 mm/slub.c:6566)\npskb_expand_head (net/core/skbuff.c:2335)\n__pskb_pull_tail (net/core/skbuff.c:2878 (discriminator 4))\n__mld_query_work (net/ipv6/mcast.c:1495 (discriminator 1))\nmld_query_work (net/ipv6/mcast.c:1563)\nprocess_one_work (kernel/workqueue.c:3314)\nworker_thread (kernel/workqueue.c:3397 kernel/workqueue.c:3478)\nkthread (kernel/kthread.c:436)\nret_from_fork (arch/x86/kernel/process.c:158)\nret_from_fork_asm (arch/x86/entry/entry_64.S:245)","modified":"2026-06-27T12:02:28.434574625Z","published":"2026-06-25T08:39:59.115Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53275.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/087dbacf897c020f438f780f0a4a8aa73b6d7c5a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/1354271c89d0e5fbf8b3d94097ff0216695209c7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2a613bf497029d555a7428406aa8cdb84a503cea"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4203806f700bb44ea0b05d484d9d40044b47fb04"},{"type":"WEB","url":"https://git.kernel.org/stable/c/53baa63a4183291574483f89583dbef13677a2c4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/791c91dc7a9dfb2457d5e29b8216a6484b9c4b40"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b2eb8886200b907fc71806869620609f0f4cacb0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53275.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53275"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"97300b5fdfe28c6edae926926f9467a27cf5889c"},{"fixed":"1354271c89d0e5fbf8b3d94097ff0216695209c7"},{"fixed":"53baa63a4183291574483f89583dbef13677a2c4"},{"fixed":"2a613bf497029d555a7428406aa8cdb84a503cea"},{"fixed":"b2eb8886200b907fc71806869620609f0f4cacb0"},{"fixed":"4203806f700bb44ea0b05d484d9d40044b47fb04"},{"fixed":"087dbacf897c020f438f780f0a4a8aa73b6d7c5a"},{"fixed":"791c91dc7a9dfb2457d5e29b8216a6484b9c4b40"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-53275.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.6.15"},{"fixed":"5.15.210"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.176"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.143"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.94"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.36"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.0.13"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-53275.json"}}],"schema_version":"1.7.5"}