{"api_version":"1","generated_at":"2026-10-20T23:11:52+00:00","cve":"CVE-2026-98442","urls":{"html":"https://cve.report/CVE-2026-98442","api":"https://cve.report/api/cve/CVE-2026-98442.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-98442","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-98442"},"summary":{"title":"net/sched: act_ct: fix helper UAF due to extensions realloc","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: act_ct: fix helper UAF due to extensions realloc\n\nWhile calling the helpers, a raw pointer to the extensions area is\nwired into expectations list:\n\n  -> nf_ct_helper()\n   -> helper->help()\n    -> nf_ct_expect_related_report()\n     -> nf_ct_expect_insert()\n      -> hlist_add_head_rcu(&exp->lnode, &master_help->expectations)\n\nIn case the connection is not confirmed yet, more extensions can be\nadded afterwards with *_ext_add() calls reallocating the extension\nspace and leaving the now invalid pointer in the expectations list\nthat is later accessed while removing the expectation.\n\nMake sure that helpers are called at the end after all the other\nextensions are already added.\n\nNote that the helper rejection now leaves the mark and labels set,\nbut that's not different from how the NAT was handled before or how\nthe mark and the labels were handled on confirmation failure.  And\nthere are no atomicity guarantees provided by the API anyway.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-10-18 16:16:54","updated_at":"2026-10-19 10:18:52"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/1679bbf5fbeac52a310b1a58b2b301bbf388bdbf","name":"https://git.kernel.org/stable/c/1679bbf5fbeac52a310b1a58b2b301bbf388bdbf","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/dad19b59da050cb60d3f7023dac2a042a84bf0bd","name":"https://git.kernel.org/stable/c/dad19b59da050cb60d3f7023dac2a042a84bf0bd","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/812c16a255e7773a544e88b39ae6daed25544d30","name":"https://git.kernel.org/stable/c/812c16a255e7773a544e88b39ae6daed25544d30","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/8988f4d11f3fba0ab38122178836c683ad516a05","name":"https://git.kernel.org/stable/c/8988f4d11f3fba0ab38122178836c683ad516a05","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98442","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98442","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected a21b06e7319129994f339ed47f512bbe57b77f5b 1679bbf5fbeac52a310b1a58b2b301bbf388bdbf git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected a21b06e7319129994f339ed47f512bbe57b77f5b 812c16a255e7773a544e88b39ae6daed25544d30 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected a21b06e7319129994f339ed47f512bbe57b77f5b 8988f4d11f3fba0ab38122178836c683ad516a05 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected a21b06e7319129994f339ed47f512bbe57b77f5b dad19b59da050cb60d3f7023dac2a042a84bf0bd git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.2","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.2 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.112 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.55 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.9 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/sched/act_ct.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"1679bbf5fbeac52a310b1a58b2b301bbf388bdbf","status":"affected","version":"a21b06e7319129994f339ed47f512bbe57b77f5b","versionType":"git"},{"lessThan":"812c16a255e7773a544e88b39ae6daed25544d30","status":"affected","version":"a21b06e7319129994f339ed47f512bbe57b77f5b","versionType":"git"},{"lessThan":"8988f4d11f3fba0ab38122178836c683ad516a05","status":"affected","version":"a21b06e7319129994f339ed47f512bbe57b77f5b","versionType":"git"},{"lessThan":"dad19b59da050cb60d3f7023dac2a042a84bf0bd","status":"affected","version":"a21b06e7319129994f339ed47f512bbe57b77f5b","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/sched/act_ct.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.2"},{"lessThan":"6.2","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.112","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.55","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.9","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.112","versionStartIncluding":"6.2","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.55","versionStartIncluding":"6.2","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.9","versionStartIncluding":"6.2","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3","versionStartIncluding":"6.2","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: act_ct: fix helper UAF due to extensions realloc\n\nWhile calling the helpers, a raw pointer to the extensions area is\nwired into expectations list:\n\n  -> nf_ct_helper()\n   -> helper->help()\n    -> nf_ct_expect_related_report()\n     -> nf_ct_expect_insert()\n      -> hlist_add_head_rcu(&exp->lnode, &master_help->expectations)\n\nIn case the connection is not confirmed yet, more extensions can be\nadded afterwards with *_ext_add() calls reallocating the extension\nspace and leaving the now invalid pointer in the expectations list\nthat is later accessed while removing the expectation.\n\nMake sure that helpers are called at the end after all the other\nextensions are already added.\n\nNote that the helper rejection now leaves the mark and labels set,\nbut that's not different from how the NAT was handled before or how\nthe mark and the labels were handled on confirmation failure.  And\nthere are no atomicity guarantees provided by the API anyway."}],"providerMetadata":{"dateUpdated":"2026-10-19T09:19:37.941Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/1679bbf5fbeac52a310b1a58b2b301bbf388bdbf"},{"url":"https://git.kernel.org/stable/c/812c16a255e7773a544e88b39ae6daed25544d30"},{"url":"https://git.kernel.org/stable/c/8988f4d11f3fba0ab38122178836c683ad516a05"},{"url":"https://git.kernel.org/stable/c/dad19b59da050cb60d3f7023dac2a042a84bf0bd"}],"title":"net/sched: act_ct: fix helper UAF due to extensions realloc","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-98442","datePublished":"2026-10-18T15:14:52.614Z","dateReserved":"2026-09-25T10:25:14.349Z","dateUpdated":"2026-10-19T09:19:37.941Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-10-18 16:16:54","lastModifiedDate":"2026-10-19 10:18:52","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"98442","Ordinal":"1","Title":"net/sched: act_ct: fix helper UAF due to extensions realloc","CVE":"CVE-2026-98442","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"98442","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: act_ct: fix helper UAF due to extensions realloc\n\nWhile calling the helpers, a raw pointer to the extensions area is\nwired into expectations list:\n\n  -> nf_ct_helper()\n   -> helper->help()\n    -> nf_ct_expect_related_report()\n     -> nf_ct_expect_insert()\n      -> hlist_add_head_rcu(&exp->lnode, &master_help->expectations)\n\nIn case the connection is not confirmed yet, more extensions can be\nadded afterwards with *_ext_add() calls reallocating the extension\nspace and leaving the now invalid pointer in the expectations list\nthat is later accessed while removing the expectation.\n\nMake sure that helpers are called at the end after all the other\nextensions are already added.\n\nNote that the helper rejection now leaves the mark and labels set,\nbut that's not different from how the NAT was handled before or how\nthe mark and the labels were handled on confirmation failure.  And\nthere are no atomicity guarantees provided by the API anyway.","Type":"Description","Title":"net/sched: act_ct: fix helper UAF due to extensions realloc"}]}}}