{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-23231", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-01-13T15:37:45.988Z", "datePublished": "2026-03-04T12:58:42.029Z", "dateUpdated": "2026-05-11T22:02:51.735Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-05-11T22:02:51.735Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_tables: fix use-after-free in nf_tables_addchain()\n\nnf_tables_addchain() publishes the chain to table->chains via\nlist_add_tail_rcu() (in nft_chain_add()) before registering hooks.\nIf nf_tables_register_hook() then fails, the error path calls\nnft_chain_del() (list_del_rcu()) followed by nf_tables_chain_destroy()\nwith no RCU grace period in between.\n\nThis creates two use-after-free conditions:\n\n 1) Control-plane: nf_tables_dump_chains() traverses table->chains\n under rcu_read_lock(). A concurrent dump can still be walking\n the chain when the error path frees it.\n\n 2) Packet path: for NFPROTO_INET, nf_register_net_hook() briefly\n installs the IPv4 hook before IPv6 registration fails. Packets\n entering nft_do_chain() via the transient IPv4 hook can still be\n dereferencing chain->blob_gen_X when the error path frees the\n chain.\n\nAdd synchronize_rcu() between nft_chain_del() and the chain destroy\nso that all RCU readers -- both dump threads and in-flight packet\nevaluation -- have finished before the chain is freed."}], "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"}}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/netfilter/nf_tables_api.c"], "versions": [{"version": "91c7b38dc9f0de4f7f444b796d14476bc12df7bc", "lessThan": "2a6586ecfa4ce1413daaafee250d2590e05f1a33", "status": "affected", "versionType": "git"}, {"version": "91c7b38dc9f0de4f7f444b796d14476bc12df7bc", "lessThan": "7017745068a9068904e1e7a1b170a5785647cc81", "status": "affected", "versionType": "git"}, {"version": "91c7b38dc9f0de4f7f444b796d14476bc12df7bc", "lessThan": "f3fe58ce37926a10115ede527d59b91bcc05400a", "status": "affected", "versionType": "git"}, {"version": "91c7b38dc9f0de4f7f444b796d14476bc12df7bc", "lessThan": "dbd0af8083dd201f07c49110b2ee93710abdff28", "status": "affected", "versionType": "git"}, {"version": "91c7b38dc9f0de4f7f444b796d14476bc12df7bc", "lessThan": "2f9a4ffeb763aec822f8ff3d1e82202d27d46d4b", "status": "affected", "versionType": "git"}, {"version": "91c7b38dc9f0de4f7f444b796d14476bc12df7bc", "lessThan": "71e99ee20fc3f662555118cf1159443250647533", "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_tables_api.c"], "versions": [{"version": "3.16", "status": "affected"}, {"version": "0", "lessThan": "3.16", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.165", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.128", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.75", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.14", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.19.4", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.0", "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": "3.16", "versionEndExcluding": "6.1.165"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.16", "versionEndExcluding": "6.6.128"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.16", "versionEndExcluding": "6.12.75"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.16", "versionEndExcluding": "6.18.14"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.16", "versionEndExcluding": "6.19.4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.16", "versionEndExcluding": "7.0"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/2a6586ecfa4ce1413daaafee250d2590e05f1a33"}, {"url": "https://git.kernel.org/stable/c/7017745068a9068904e1e7a1b170a5785647cc81"}, {"url": "https://git.kernel.org/stable/c/f3fe58ce37926a10115ede527d59b91bcc05400a"}, {"url": "https://git.kernel.org/stable/c/dbd0af8083dd201f07c49110b2ee93710abdff28"}, {"url": "https://git.kernel.org/stable/c/2f9a4ffeb763aec822f8ff3d1e82202d27d46d4b"}, {"url": "https://git.kernel.org/stable/c/71e99ee20fc3f662555118cf1159443250647533"}], "title": "netfilter: nf_tables: fix use-after-free in nf_tables_addchain()", "x_generator": {"engine": "bippy-1.2.0"}}}}

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{"configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "E51277CF-00C8-4E26-BC0E-6A90823CCC3E", "versionEndExcluding": "6.1.165", "versionStartIncluding": "3.16", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "851E9353-6C09-4CC9-877E-E09DB164A3C2", "versionEndExcluding": "6.6.128", "versionStartIncluding": "6.2", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "BCE16369-98ED-41CF-8995-DFDC10B288D2", "versionEndExcluding": "6.12.75", "versionStartIncluding": "6.7", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "BF463CB7-1F58-4607-B847-77ED23E4B9B7", "versionEndExcluding": "6.18.14", "versionStartIncluding": "6.13", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "672A3E79-EC03-479D-8503-361DFBDC8092", "versionEndExcluding": "6.19.4", "versionStartIncluding": "6.19", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_tables: fix use-after-free in nf_tables_addchain()\n\nnf_tables_addchain() publishes the chain to table->chains via\nlist_add_tail_rcu() (in nft_chain_add()) before registering hooks.\nIf nf_tables_register_hook() then fails, the error path calls\nnft_chain_del() (list_del_rcu()) followed by nf_tables_chain_destroy()\nwith no RCU grace period in between.\n\nThis creates two use-after-free conditions:\n\n 1) Control-plane: nf_tables_dump_chains() traverses table->chains\n under rcu_read_lock(). A concurrent dump can still be walking\n the chain when the error path frees it.\n\n 2) Packet path: for NFPROTO_INET, nf_register_net_hook() briefly\n installs the IPv4 hook before IPv6 registration fails. Packets\n entering nft_do_chain() via the transient IPv4 hook can still be\n dereferencing chain->blob_gen_X when the error path frees the\n chain.\n\nAdd synchronize_rcu() between nft_chain_del() and the chain destroy\nso that all RCU readers -- both dump threads and in-flight packet\nevaluation -- have finished before the chain is freed."}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nnetfilter: nf_tables: corrige uso despu\u00e9s de liberaci\u00f3n en nf_tables_addchain()\n\nnf_tables_addchain() publica la cadena en table->chains a trav\u00e9s de list_add_tail_rcu() (en nft_chain_add()) antes de registrar los ganchos. Si nf_tables_register_hook() falla entonces, la ruta de error llama a nft_chain_del() (list_del_rcu()) seguido de nf_tables_chain_destroy() sin un per\u00edodo de gracia RCU intermedio.\n\nEsto crea dos condiciones de uso despu\u00e9s de liberaci\u00f3n:\n\n1) Plano de control: nf_tables_dump_chains() recorre table->chains bajo rcu_read_lock(). Un volcado concurrente a\u00fan puede estar recorriendo la cadena cuando la ruta de error la libera.\n\n2) Ruta de paquetes: para NFPROTO_INET, nf_register_net_hook() instala brevemente el gancho IPv4 antes de que falle el registro de IPv6. Los paquetes que entran en nft_do_chain() a trav\u00e9s del gancho IPv4 transitorio a\u00fan pueden estar desreferenciando chain->blob_gen_X cuando la ruta de error libera la cadena.\n\nA\u00f1adir synchronize_rcu() entre nft_chain_del() y la destrucci\u00f3n de la cadena para que todos los lectores RCU -- tanto los hilos de volcado como la evaluaci\u00f3n de paquetes en curso -- hayan terminado antes de que la cadena sea liberada."}], "id": "CVE-2026-23231", "lastModified": "2026-04-02T15:16:24.693", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}, {"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "nvd@nist.gov", "type": "Primary"}]}, "published": "2026-03-04T13:15:58.137", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/2a6586ecfa4ce1413daaafee250d2590e05f1a33"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/2f9a4ffeb763aec822f8ff3d1e82202d27d46d4b"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/7017745068a9068904e1e7a1b170a5785647cc81"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/71e99ee20fc3f662555118cf1159443250647533"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/dbd0af8083dd201f07c49110b2ee93710abdff28"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/f3fe58ce37926a10115ede527d59b91bcc05400a"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-416"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: netfilter: nf_tables: fix use-after-free in nf_tables_addchain()", "id": "2444376", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2444376"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.0", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "status": "draft"}, "details": ["No description is available for this CVE."], "name": "CVE-2026-23231", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-03-04T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-23231\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-23231\nhttps://lore.kernel.org/linux-cve-announce/2026030436-CVE-2026-23231-1a96@gregkh/T"], "threat_severity": "Important"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[91c7b38dc9f0de4f7f444b796d14476bc12df7bc,2a6586ecfa4ce1413daaafee250d2590e05f1a33)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[91c7b38dc9f0de4f7f444b796d14476bc12df7bc,7017745068a9068904e1e7a1b170a5785647cc81)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[91c7b38dc9f0de4f7f444b796d14476bc12df7bc,f3fe58ce37926a10115ede527d59b91bcc05400a)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[91c7b38dc9f0de4f7f444b796d14476bc12df7bc,dbd0af8083dd201f07c49110b2ee93710abdff28)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[91c7b38dc9f0de4f7f444b796d14476bc12df7bc,2f9a4ffeb763aec822f8ff3d1e82202d27d46d4b)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[91c7b38dc9f0de4f7f444b796d14476bc12df7bc,71e99ee20fc3f662555118cf1159443250647533)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "3.16"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,3.16)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.1.165,6.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.6.128,6.7.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.75,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.14,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.19.4,6.20.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.0-rc1,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "analysis": {"en": {"generated_at": "2026-04-16T13:35:17.617054+00:00", "value": {"mitigation_remediation": ["Update the Linux kernel to a version that incorporates the RCU synchronization fix for nf_tables_addchain (see the commit links in the advisory).", "If a kernel upgrade cannot be performed immediately, avoid configuring new nf_tables chains or disable nf_tables functionality until the patch is available.", "If a system relies on a distribution with managed kernel updates, configure it to apply updates automatically so the RCU synchronization fix is installed as soon as available."], "summary": {"action": "Immediate Patch", "impact": "Kernel crash or denial-of-service due to use\u2011after\u2011free in nf_tables"}, "threat_synthesis": {"affected_systems": "The flaw affects the Linux kernel broadly; no specific version numbers are listed in the advisory, but all kernel releases that include the legacy nf_tables implementation are potentially vulnerable. Linux kernel users who employ nf_tables for firewall or packet filtering should be aware that any chain configuration could trigger the bug if a registration fails during hook installation.", "description_and_impact": "A use\u2011after\u2011free flaw (CWE\u2011416) exists in the nf_tables component of the Linux kernel where a chain added to a table can be freed while still being read by RCU code paths, both on the control plane and during packet processing. Based on the description, it is inferred that a local attacker could trigger a kernel crash by causing a chain registration failure while the chain is still being accessed. The vulnerability may lead to denial\u2011of\u2011service rather than privilege escalation.", "risk_and_exploitability": "The vulnerability\u2019s CVSS score of 7.8 places it in the high\u2011risk category, and the reported exploitation probability is very low, estimated under 1%. It is not listed in the CISA KEV catalog. The lack of an RCU grace period means any concurrent read activity could trigger a use\u2011after\u2011free while the kernel processes control\u2011plane or packet\u2011path requests. Attackers with local privileges could exploit the race by creating a chain whose registration fails, causing the kernel to crash. The danger lies primarily in system instability and denial\u2011of\u2011service."}}}}, "created": "2026-03-04T21:03:32.365609+00:00", "updated": "2026-04-16T13:45:21.945295+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}