{ "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" } } } }