{"id":"CVE-2026-64563","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-64563","summary":"rhashtable: clear stale iter->p on table restart","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nrhashtable: clear stale iter->p on table restart\n\nrhashtable_walk_start_check() has two restart paths when resuming a walk.\nWhen iter->walker.tbl is valid, it re-validates iter->p against the table\nand sets iter->p = NULL if the object is gone.  When iter->walker.tbl is\nNULL (table was freed during resize), it resets slot and skip but forgets\nto clear iter->p.\n\nrhashtable_walk_next() then dereferences the stale iter->p, reading\nfreed memory.  This is a use-after-free.\n\nAny caller that does multi-fragment rhashtable walks across\nwalk_stop/walk_start boundaries is affected.  Concrete cases include\nnetlink_diag (__netlink_diag_dump in net/netlink/diag.c) and TIPC\n(tipc_nl_sk_walk in net/tipc/socket.c).\n\nCrash stack (netlink_diag):\n  BUG: KASAN: slab-use-after-free in rhashtable_walk_next+0x365/0x3c0\n  Read of size 8 at addr ffff88801a9d2438 (freed kmalloc-2k, offset 1080)\n  Call Trace:\n   rhashtable_walk_next+0x365/0x3c0 (lib/rhashtable.c:1016)\n   __netlink_diag_dump+0x160/0x760 (net/netlink/diag.c:122)\n   netlink_diag_dump+0xc2/0x240\n   netlink_dump+0x5bc/0x1270\n   netlink_recvmsg+0x7a3/0x980\n   sock_recvmsg+0x1bc/0x200\n   __sys_recvfrom+0x1d4/0x2c0","published":"2026-08-04T06:23:22.601Z","modified":"2026-08-09T03:47:25.675353416Z","cvss":{"score":7.8,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"6.18.42"}],"fix":null,"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/3ff7c1dbf722cf3fa538672452ba182318e0fcc3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4169d9fb92f313ff8e7e83d733c1ecdcc93eebd3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8173f7e2ce67e6ca1d4763f3da14e5b01ce77456"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64563.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64563"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-09T03:47:25.675353416Z"}}