{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-64563","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-07-19T15:36:31.797Z","datePublished":"2026-08-04T06:23:22.601Z","dateUpdated":"2026-08-19T16:28:34.797Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-19T16:28:34.797Z"},"descriptions":[{"lang":"en","value":"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"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - Triggered via local netlink sock_diag dumps (e.g. netlink_diag over NETLINK_SOCK_DIAG) and similar local dump walkers such as TIPC_NL_SOCK_GET; not reachable from remote packet processing.\nAC:L - Attacker controls both sides of the race by running a multi-fragment rhashtable dump while concurrently creating/destroying netlink (or TIPC) sockets to force table resize and free the walked object.\nPR:L - An unprivileged local user can open NETLINK_SOCK_DIAG and dump without CAP_NET_ADMIN; CAP_NET_ADMIN is only required for SOCK_DESTROY, and TIPC_NL_SOCK_GET likewise has no admin permission flag.\nUI:N - Exploitation requires only attacker-issued syscalls (netlink dump plus concurrent socket churn); no victim action is needed.\nS:U - Impact is memory corruption within the host kernel authority (local privilege escalation/crash), not a cross-boundary escape such as guest-to-host or IOMMU bypass.\nC:H - Use-after-free read of a freed hashed object (e.g. netlink_sock) can be reclaimed via heap spray, yielding an arbitrary read primitive through subsequent walk/diag use of the corrupted pointer.\nI:H - UAF on a reclaimable slab object enables heap spraying and fake-object injection into the walk path, which can be leveraged for arbitrary write or control-flow hijacking.\nA:H - The demonstrated KASAN slab-use-after-free in rhashtable_walk_next can oops/panic the kernel, and UAFs remain crashable even when not fully exploited."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["lib/rhashtable.c"],"versions":[{"version":"5d240a8936f6a1d3ece06701e8c4d830a2eca8a8","lessThan":"ba510b5e9fe396497d31162acb579f210adfe6c8","status":"affected","versionType":"git"},{"version":"5d240a8936f6a1d3ece06701e8c4d830a2eca8a8","lessThan":"a0406c40c6638c5ae50257db6297b2fba6c9ba16","status":"affected","versionType":"git"},{"version":"5d240a8936f6a1d3ece06701e8c4d830a2eca8a8","lessThan":"0955b65c2b47c30b439e2cf1b1e375073aa0413a","status":"affected","versionType":"git"},{"version":"5d240a8936f6a1d3ece06701e8c4d830a2eca8a8","lessThan":"c39643ad99fea749be50615550e8f0e6d6e60694","status":"affected","versionType":"git"},{"version":"5d240a8936f6a1d3ece06701e8c4d830a2eca8a8","lessThan":"042fda5c088015f18838e5c692659a7be60aeb26","status":"affected","versionType":"git"},{"version":"5d240a8936f6a1d3ece06701e8c4d830a2eca8a8","lessThan":"3ff7c1dbf722cf3fa538672452ba182318e0fcc3","status":"affected","versionType":"git"},{"version":"5d240a8936f6a1d3ece06701e8c4d830a2eca8a8","lessThan":"4169d9fb92f313ff8e7e83d733c1ecdcc93eebd3","status":"affected","versionType":"git"},{"version":"5d240a8936f6a1d3ece06701e8c4d830a2eca8a8","lessThan":"8173f7e2ce67e6ca1d4763f3da14e5b01ce77456","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["lib/rhashtable.c"],"versions":[{"version":"4.18","status":"affected"},{"version":"0","lessThan":"4.18","status":"unaffected","versionType":"semver"},{"version":"5.10.265","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.216","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.183","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.151","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.103","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.42","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.1.6","lessThanOrEqual":"7.1.*","status":"unaffected","versionType":"semver"},{"version":"7.2","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.18","versionEndExcluding":"5.10.265"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.18","versionEndExcluding":"5.15.216"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.18","versionEndExcluding":"6.1.183"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.18","versionEndExcluding":"6.6.151"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.18","versionEndExcluding":"6.12.103"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.18","versionEndExcluding":"6.18.42"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.18","versionEndExcluding":"7.1.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.18","versionEndExcluding":"7.2"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/ba510b5e9fe396497d31162acb579f210adfe6c8"},{"url":"https://git.kernel.org/stable/c/a0406c40c6638c5ae50257db6297b2fba6c9ba16"},{"url":"https://git.kernel.org/stable/c/0955b65c2b47c30b439e2cf1b1e375073aa0413a"},{"url":"https://git.kernel.org/stable/c/c39643ad99fea749be50615550e8f0e6d6e60694"},{"url":"https://git.kernel.org/stable/c/042fda5c088015f18838e5c692659a7be60aeb26"},{"url":"https://git.kernel.org/stable/c/3ff7c1dbf722cf3fa538672452ba182318e0fcc3"},{"url":"https://git.kernel.org/stable/c/4169d9fb92f313ff8e7e83d733c1ecdcc93eebd3"},{"url":"https://git.kernel.org/stable/c/8173f7e2ce67e6ca1d4763f3da14e5b01ce77456"}],"title":"rhashtable: clear stale iter->p on table restart","x_generator":{"engine":"bippy-1.2.0"}}}}