{"id":"CVE-2026-98230","published":"2026-10-06T09:18:10.397","lastModified":"2026-10-07T07:17:05.663","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: use hlist_del_init_rcu for state_cache and state_cache_input\n\nCommit 14acf9652e56 (\"xfrm: defensively unhash xfrm_state lists in\n__xfrm_state_delete\") converted bydst/bysrc/byseq/byspi from\nhlist_del_rcu() to hlist_del_init_rcu() so that a second\n__xfrm_state_delete() on the same object becomes a no-op rather than a\nwrite through LIST_POISON pprev. It missed state_cache and\nstate_cache_input, which kept hlist_del_rcu():\n\n- hlist_del_rcu() leaves pprev = LIST_POISON2 (non-NULL), so\n  hlist_unhashed() returns false.\n- hlist_del_init_rcu() leaves pprev = NULL, so hlist_unhashed()\n  returns true.\n\nA second __xfrm_state_delete() therefore enters __hlist_del() on the\nalready-deleted state_cache/state_cache_input nodes and does\nWRITE_ONCE(*pprev, next) through LIST_POISON2 — a write use-after-free\nonce the slab is reused. The corruption can in turn cause a subsequent\nhlist_for_each_entry_rcu traversal to follow a dangling next pointer,\nproducing the read use-after-free reported in xfrm_input_state_lookup().\n\nSwitch state_cache and state_cache_input to hlist_del_init_rcu() to\nmatch the other four lists, closing the write use-after-free and, with\nit, the read use-after-free it spawns.","cvssScore":7,"cvssSeverity":"HIGH","cvssVector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/2afb8dc1f4390f164db8352f8e685e126e9db566","tags":[]},{"url":"https://git.kernel.org/stable/c/4748c27e2e6a1969e02f1df46e62f79d2799b80b","tags":[]},{"url":"https://git.kernel.org/stable/c/9b74a47a4cbd0d29faff4f3b199212c73e6b6220","tags":[]},{"url":"https://git.kernel.org/stable/c/fb38fb7420d5f7192f9e2b6ac835ede149cd7ac5","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":null}