{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-74746", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-15T05:44:03.931Z", "datePublished": "2026-08-26T14:36:55.963Z", "dateUpdated": "2026-10-16T19:26:23.781Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-27T05:01:07.405Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: flowtable: publish GC-visible tuple last\n\nnf_flow_table_iterate() only treats original-direction tuple nodes as\nowning entries. Publishing the original node first lets GC observe and\nfree a flow while flow_offload_add() is still inserting the reply node.\nPublish the reply node first and the original node last so GC never\nsees a partially installed flow.\n\nKASAN can trigger slab-use-after-free read and write reports in the\nflowtable/rhashtable path (rht_deferred_worker, jhash, flow_offload_del,\nflow_offload_lookup, etc.)." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL" }, "scenarios": [ { "lang": "en", "value": "AV:N - flow_offload_add runs from nft_flow_offload_eval on the FORWARD hook and from tc act_ct during softirq packet processing when remote TCP/UDP traffic creates new offloaded conntrack flows on nftables flowtable routers/gateways, not through netlink configuration APIs.\nAC:L - The attacker controls when flows are offloaded (packet rate/timing) and can race connection teardown so nf_flow_table_gc_run observes a partially installed original tuple while reply insertion is still in progress; both the insert and GC sides of the race are attacker-driven.\nPR:N - On the intended edge-router/OpenWrt deployment, nftables flow offload is an administrator prerequisite; a remote sender needs no local account, authentication, or CAP_NET_ADMIN on the victim to trigger flow_offload_add while forwarding traffic.\nUI:N - Exploitation requires only sending network packets processed automatically on the forwarding or ingress path; no victim must open files, mount filesystems, or take any interactive action beyond normal traffic through the router.\nS:U - Slab use-after-free in the flowtable rhashtable/GC path affects only in-kernel memory on the affected host; this is standard kernel compromise within one security authority, not a VM escape, IOMMU bypass, or cross-boundary sandbox break.\nC:H - The fix commit documents KASAN slab-use-after-free read and write reports in rht_deferred_worker, jhash, flow_offload_del, and flow_offload_lookup; UAF on flow_offload kmem-cache objects enables arbitrary kernel memory disclosure via heap grooming.\nI:H - Freed flow_offload structures remain reachable during concurrent rhashtable insert/remove and deferred worker operations, providing attacker-influenceable heap corruption that can be groomed into arbitrary kernel writes and control-flow hijack.\nA:H - Concurrent GC freeing of a partially inserted flow while flow_offload_add or rhashtable workers still access it causes kernel oops/panic and reliable denial of service; UAF on the flow offload path can crash forwarding routers under sustained malicious traffic." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/netfilter/nf_flow_table_core.c" ], "versions": [ { "version": "ac2a66665e231847cab11b8c8e844ce43207dd2e", "lessThan": "0a00254585827f1695aa2700114af622ea754cfa", "status": "affected", "versionType": "git" }, { "version": "ac2a66665e231847cab11b8c8e844ce43207dd2e", "lessThan": "be345dcbddb4643a54252b954af974b16eda8f91", "status": "affected", "versionType": "git" }, { "version": "ac2a66665e231847cab11b8c8e844ce43207dd2e", "lessThan": "211ee5d998d92a7d548811939c65942d06c146e4", "status": "affected", "versionType": "git" }, { "version": "ac2a66665e231847cab11b8c8e844ce43207dd2e", "lessThan": "d37917e7bebe078f3c17e47fd6fc1c9f6e8497b2", "status": "affected", "versionType": "git" }, { "version": "ac2a66665e231847cab11b8c8e844ce43207dd2e", "lessThan": "972fdf7c4f5c282a239c88fea614b056c33dc025", "status": "affected", "versionType": "git" }, { "version": "ac2a66665e231847cab11b8c8e844ce43207dd2e", "lessThan": "d9d3050a70efe217e73a0751e55fdae6a7092620", "status": "affected", "versionType": "git" }, { "version": "ac2a66665e231847cab11b8c8e844ce43207dd2e", "lessThan": "d16b71231e65cb05daea2b45701fcf09cef041e7", "status": "affected", "versionType": "git" }, { "version": "ac2a66665e231847cab11b8c8e844ce43207dd2e", "lessThan": "2014ac62df9d45bb9a004a043e85df7be09ed780", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/netfilter/nf_flow_table_core.c" ], "versions": [ { "version": "4.16", "status": "affected" }, { "version": "0", "lessThan": "4.16", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.266", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.217", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.184", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.153", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.105", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.46", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.10", "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": "4.16", "versionEndExcluding": "5.10.266" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "5.15.217" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "6.1.184" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "6.6.153" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "6.12.105" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "6.18.46" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "7.1.10" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/0a00254585827f1695aa2700114af622ea754cfa" }, { "url": "https://git.kernel.org/stable/c/be345dcbddb4643a54252b954af974b16eda8f91" }, { "url": "https://git.kernel.org/stable/c/211ee5d998d92a7d548811939c65942d06c146e4" }, { "url": "https://git.kernel.org/stable/c/d37917e7bebe078f3c17e47fd6fc1c9f6e8497b2" }, { "url": "https://git.kernel.org/stable/c/972fdf7c4f5c282a239c88fea614b056c33dc025" }, { "url": "https://git.kernel.org/stable/c/d9d3050a70efe217e73a0751e55fdae6a7092620" }, { "url": "https://git.kernel.org/stable/c/d16b71231e65cb05daea2b45701fcf09cef041e7" }, { "url": "https://git.kernel.org/stable/c/2014ac62df9d45bb9a004a043e85df7be09ed780" } ], "title": "netfilter: flowtable: publish GC-visible tuple last", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2026-74746", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "yes" }, { "Technical Impact": "total" } ], "version": "2.0.3", "timestamp": "2026-10-16T19:16:14.907909Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-16T19:26:23.781Z" } } ] } }