CVE-2025-40206

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2025-40206", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T07:20:57.179Z", "datePublished": "2025-11-12T21:56:35.675Z", "dateUpdated": "2026-10-15T22:02:40.982Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-23T12:45:25.956Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nft_objref: validate objref and objrefmap expressions\n\nReferencing a synproxy stateful object from OUTPUT hook causes kernel\ncrash due to infinite recursive calls:\n\nBUG: TASK stack guard page was hit at 000000008bda5b8c (stack is 000000003ab1c4a5..00000000494d8b12)\n[...]\nCall Trace:\n __find_rr_leaf+0x99/0x230\n fib6_table_lookup+0x13b/0x2d0\n ip6_pol_route+0xa4/0x400\n fib6_rule_lookup+0x156/0x240\n ip6_route_output_flags+0xc6/0x150\n __nf_ip6_route+0x23/0x50\n synproxy_send_tcp_ipv6+0x106/0x200\n synproxy_send_client_synack_ipv6+0x1aa/0x1f0\n nft_synproxy_do_eval+0x263/0x310\n nft_do_chain+0x5a8/0x5f0 [nf_tables\n nft_do_chain_inet+0x98/0x110\n nf_hook_slow+0x43/0xc0\n __ip6_local_out+0xf0/0x170\n ip6_local_out+0x17/0x70\n synproxy_send_tcp_ipv6+0x1a2/0x200\n synproxy_send_client_synack_ipv6+0x1aa/0x1f0\n[...]\n\nImplement objref and objrefmap expression validate functions.\n\nCurrently, only NFT_OBJECT_SYNPROXY object type requires validation.\nThis will also handle a jump to a chain using a synproxy object from the\nOUTPUT hook.\n\nNow when trying to reference a synproxy object in the OUTPUT hook, nft\nwill produce the following error:\n\nsynproxy_crash.nft: Error: Could not process rule: Operation not supported\n synproxy name mysynproxy\n ^^^^^^^^^^^^^^^^^^^^^^^^"}], "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 - The flaw is enabled through an nftables ruleset installed over the NFNL_SUBSYS_NFTABLES netlink socket, and triggered by a locally-generated TCP SYN traversing the OUTPUT hook. Per netfilter/nftables convention this is a local attack surface, not a remotely reachable one.\nAC:L - Exploitation is fully deterministic \u2014 add a synproxy object reference to an OUTPUT base chain and emit any TCP SYN; there is no race, no memory-layout dependency, and no bound on the recursion depth. CONFIG_NFT_SYNPROXY is standard and autoloadable on distribution kernels.\nPR:L - nfnetlink_rcv checks netlink_net_capable(skb, CAP_NET_ADMIN), which evaluates against the network namespace's owning user namespace, so any unprivileged local user obtains it via `unshare -Urn`; nft_synproxy_do_init imposes no init_user_ns requirement. The resulting stack overflow is not confined to the namespace and takes down the host.\nUI:N - The attacker performs both steps \u2014 installing the rule and emitting the triggering SYN \u2014 with no action required from any other user or administrator.\nS:U - The recursion, the stack exhaustion, and the resulting panic all occur within the kernel's own security authority; no hypervisor, IOMMU, or other trust boundary is crossed.\nC:H - The unbounded recursion exhausts the kernel stack, and on the many embedded/IoT/automotive configurations lacking CONFIG_VMAP_STACK (arm32 without ARM_HAS_GROUP_RELOCS, and architectures with no VMAP_STACK support) it runs past the stack into adjacent kernel pages rather than into a guard page, corrupting neighbouring structures that can be leveraged for kernel memory disclosure.\nI:H - On those same non-VMAP_STACK configurations the overrun writes attacker-influenced frame contents \u2014 struct flowi6 built from the attacker's SYN addresses/ports, synproxy_options with attacker-chosen MSS/wscale/timestamps, and nft_regs \u2014 into adjacent kernel memory, and on architectures where thread_info sits at the stack base it clobbers that first, yielding an exploitable corruption primitive.\nA:H - The infinite recursion reliably exhausts the kernel stack and hits the guard page, producing an immediate kernel panic as shown in the reporter's trace. This is a complete denial of service triggerable at will by an unprivileged local user."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/netfilter/nft_objref.c"], "versions": [{"version": "ee394f96ad7517fbc0de9106dcc7ce9efb14f264", "lessThan": "f31bcea12222a26d6f151df9c4a6d21f2eec1724", "status": "affected", "versionType": "git"}, {"version": "ee394f96ad7517fbc0de9106dcc7ce9efb14f264", "lessThan": "0028e0134c64d9ed21728341a74fcfc59cd0f944", "status": "affected", "versionType": "git"}, {"version": "ee394f96ad7517fbc0de9106dcc7ce9efb14f264", "lessThan": "7ea55a44493a5a36c3b3293b88bbe4841f9dbaf0", "status": "affected", "versionType": "git"}, {"version": "ee394f96ad7517fbc0de9106dcc7ce9efb14f264", "lessThan": "4c1cf72ec10be5a9ad264650cadffa1fbce6fabd", "status": "affected", "versionType": "git"}, {"version": "ee394f96ad7517fbc0de9106dcc7ce9efb14f264", "lessThan": "f359b809d54c6e3dd1d039b97e0b68390b0e53e4", "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/nft_objref.c"], "versions": [{"version": "5.4", "status": "affected"}, {"version": "0", "lessThan": "5.4", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.184", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.113", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.54", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.17.4", "lessThanOrEqual": "6.17.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18", "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": "5.4", "versionEndExcluding": "6.1.184"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.4", "versionEndExcluding": "6.6.113"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.4", "versionEndExcluding": "6.12.54"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.4", "versionEndExcluding": "6.17.4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.4", "versionEndExcluding": "6.18"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/f31bcea12222a26d6f151df9c4a6d21f2eec1724"}, {"url": "https://git.kernel.org/stable/c/0028e0134c64d9ed21728341a74fcfc59cd0f944"}, {"url": "https://git.kernel.org/stable/c/7ea55a44493a5a36c3b3293b88bbe4841f9dbaf0"}, {"url": "https://git.kernel.org/stable/c/4c1cf72ec10be5a9ad264650cadffa1fbce6fabd"}, {"url": "https://git.kernel.org/stable/c/f359b809d54c6e3dd1d039b97e0b68390b0e53e4"}], "title": "netfilter: nft_objref: validate objref and objrefmap expressions", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2025-40206", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2026-10-15T21:58:13.235707Z"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-15T22:02:40.982Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2025-40206", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2026-10-15T21:58:13.235707Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-15T21:58:14.211Z"}}], "cna": {"title": "netfilter: nft_objref: validate objref and objrefmap expressions", "metrics": [{"cvssV3_1": {"version": "3.1", "baseScore": 7.8, "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}, "scenarios": [{"lang": "en", "value": "AV:L - The flaw is enabled through an nftables ruleset installed over the NFNL_SUBSYS_NFTABLES netlink socket, and triggered by a locally-generated TCP SYN traversing the OUTPUT hook. Per netfilter/nftables convention this is a local attack surface, not a remotely reachable one.\nAC:L - Exploitation is fully deterministic \u2014 add a synproxy object reference to an OUTPUT base chain and emit any TCP SYN; there is no race, no memory-layout dependency, and no bound on the recursion depth. CONFIG_NFT_SYNPROXY is standard and autoloadable on distribution kernels.\nPR:L - nfnetlink_rcv checks netlink_net_capable(skb, CAP_NET_ADMIN), which evaluates against the network namespace's owning user namespace, so any unprivileged local user obtains it via `unshare -Urn`; nft_synproxy_do_init imposes no init_user_ns requirement. The resulting stack overflow is not confined to the namespace and takes down the host.\nUI:N - The attacker performs both steps \u2014 installing the rule and emitting the triggering SYN \u2014 with no action required from any other user or administrator.\nS:U - The recursion, the stack exhaustion, and the resulting panic all occur within the kernel's own security authority; no hypervisor, IOMMU, or other trust boundary is crossed.\nC:H - The unbounded recursion exhausts the kernel stack, and on the many embedded/IoT/automotive configurations lacking CONFIG_VMAP_STACK (arm32 without ARM_HAS_GROUP_RELOCS, and architectures with no VMAP_STACK support) it runs past the stack into adjacent kernel pages rather than into a guard page, corrupting neighbouring structures that can be leveraged for kernel memory disclosure.\nI:H - On those same non-VMAP_STACK configurations the overrun writes attacker-influenced frame contents \u2014 struct flowi6 built from the attacker's SYN addresses/ports, synproxy_options with attacker-chosen MSS/wscale/timestamps, and nft_regs \u2014 into adjacent kernel memory, and on architectures where thread_info sits at the stack base it clobbers that first, yielding an exploitable corruption primitive.\nA:H - The infinite recursion reliably exhausts the kernel stack and hits the guard page, producing an immediate kernel panic as shown in the reporter's trace. This is a complete denial of service triggerable at will by an unprivileged local user."}]}], "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "ee394f96ad7517fbc0de9106dcc7ce9efb14f264", "lessThan": "f31bcea12222a26d6f151df9c4a6d21f2eec1724", "versionType": "git"}, {"status": "affected", "version": "ee394f96ad7517fbc0de9106dcc7ce9efb14f264", "lessThan": "0028e0134c64d9ed21728341a74fcfc59cd0f944", "versionType": "git"}, {"status": "affected", "version": "ee394f96ad7517fbc0de9106dcc7ce9efb14f264", "lessThan": "7ea55a44493a5a36c3b3293b88bbe4841f9dbaf0", "versionType": "git"}, {"status": "affected", "version": "ee394f96ad7517fbc0de9106dcc7ce9efb14f264", "lessThan": "4c1cf72ec10be5a9ad264650cadffa1fbce6fabd", "versionType": "git"}, {"status": "affected", "version": "ee394f96ad7517fbc0de9106dcc7ce9efb14f264", "lessThan": "f359b809d54c6e3dd1d039b97e0b68390b0e53e4", "versionType": "git"}], "programFiles": ["net/netfilter/nft_objref.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "5.4"}, {"status": "unaffected", "version": "0", "lessThan": "5.4", "versionType": "semver"}, {"status": "unaffected", "version": "6.1.184", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"status": "unaffected", "version": "6.6.113", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.12.54", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.17.4", "versionType": "semver", "lessThanOrEqual": "6.17.*"}, {"status": "unaffected", "version": "6.18", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["net/netfilter/nft_objref.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/f31bcea12222a26d6f151df9c4a6d21f2eec1724"}, {"url": "https://git.kernel.org/stable/c/0028e0134c64d9ed21728341a74fcfc59cd0f944"}, {"url": "https://git.kernel.org/stable/c/7ea55a44493a5a36c3b3293b88bbe4841f9dbaf0"}, {"url": "https://git.kernel.org/stable/c/4c1cf72ec10be5a9ad264650cadffa1fbce6fabd"}, {"url": "https://git.kernel.org/stable/c/f359b809d54c6e3dd1d039b97e0b68390b0e53e4"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nft_objref: validate objref and objrefmap expressions\n\nReferencing a synproxy stateful object from OUTPUT hook causes kernel\ncrash due to infinite recursive calls:\n\nBUG: TASK stack guard page was hit at 000000008bda5b8c (stack is 000000003ab1c4a5..00000000494d8b12)\n[...]\nCall Trace:\n __find_rr_leaf+0x99/0x230\n fib6_table_lookup+0x13b/0x2d0\n ip6_pol_route+0xa4/0x400\n fib6_rule_lookup+0x156/0x240\n ip6_route_output_flags+0xc6/0x150\n __nf_ip6_route+0x23/0x50\n synproxy_send_tcp_ipv6+0x106/0x200\n synproxy_send_client_synack_ipv6+0x1aa/0x1f0\n nft_synproxy_do_eval+0x263/0x310\n nft_do_chain+0x5a8/0x5f0 [nf_tables\n nft_do_chain_inet+0x98/0x110\n nf_hook_slow+0x43/0xc0\n __ip6_local_out+0xf0/0x170\n ip6_local_out+0x17/0x70\n synproxy_send_tcp_ipv6+0x1a2/0x200\n synproxy_send_client_synack_ipv6+0x1aa/0x1f0\n[...]\n\nImplement objref and objrefmap expression validate functions.\n\nCurrently, only NFT_OBJECT_SYNPROXY object type requires validation.\nThis will also handle a jump to a chain using a synproxy object from the\nOUTPUT hook.\n\nNow when trying to reference a synproxy object in the OUTPUT hook, nft\nwill produce the following error:\n\nsynproxy_crash.nft: Error: Could not process rule: Operation not supported\n synproxy name mysynproxy\n ^^^^^^^^^^^^^^^^^^^^^^^^"}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": 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"dateReserved": "2025-04-16T07:20:57.179Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2025-11-12T21:56:35.675Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["net/netfilter/nft_objref.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "f31bcea12222a26d6f151df9c4a6d21f2eec1724", "status": "affected", "version": "ee394f96ad7517fbc0de9106dcc7ce9efb14f264", "versionType": "git"}, {"lessThan": "0028e0134c64d9ed21728341a74fcfc59cd0f944", "status": "affected", "version": "ee394f96ad7517fbc0de9106dcc7ce9efb14f264", "versionType": "git"}, {"lessThan": "7ea55a44493a5a36c3b3293b88bbe4841f9dbaf0", "status": "affected", "version": "ee394f96ad7517fbc0de9106dcc7ce9efb14f264", "versionType": "git"}, {"lessThan": "4c1cf72ec10be5a9ad264650cadffa1fbce6fabd", "status": "affected", "version": "ee394f96ad7517fbc0de9106dcc7ce9efb14f264", "versionType": "git"}, {"lessThan": "f359b809d54c6e3dd1d039b97e0b68390b0e53e4", "status": "affected", "version": "ee394f96ad7517fbc0de9106dcc7ce9efb14f264", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["net/netfilter/nft_objref.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "5.4"}, {"lessThan": "5.4", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.184", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.113", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.54", "versionType": "semver"}, {"lessThanOrEqual": "6.17.*", "status": "unaffected", "version": "6.17.4", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "6.18", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nft_objref: validate objref and objrefmap expressions\n\nReferencing a synproxy stateful object from OUTPUT hook causes kernel\ncrash due to infinite recursive calls:\n\nBUG: TASK stack guard page was hit at 000000008bda5b8c (stack is 000000003ab1c4a5..00000000494d8b12)\n[...]\nCall Trace:\n __find_rr_leaf+0x99/0x230\n fib6_table_lookup+0x13b/0x2d0\n ip6_pol_route+0xa4/0x400\n fib6_rule_lookup+0x156/0x240\n ip6_route_output_flags+0xc6/0x150\n __nf_ip6_route+0x23/0x50\n synproxy_send_tcp_ipv6+0x106/0x200\n synproxy_send_client_synack_ipv6+0x1aa/0x1f0\n nft_synproxy_do_eval+0x263/0x310\n nft_do_chain+0x5a8/0x5f0 [nf_tables\n nft_do_chain_inet+0x98/0x110\n nf_hook_slow+0x43/0xc0\n __ip6_local_out+0xf0/0x170\n ip6_local_out+0x17/0x70\n synproxy_send_tcp_ipv6+0x1a2/0x200\n synproxy_send_client_synack_ipv6+0x1aa/0x1f0\n[...]\n\nImplement objref and objrefmap expression validate functions.\n\nCurrently, only NFT_OBJECT_SYNPROXY object type requires validation.\nThis will also handle a jump to a chain using a synproxy object from the\nOUTPUT hook.\n\nNow when trying to reference a synproxy object in the OUTPUT hook, nft\nwill produce the following error:\n\nsynproxy_crash.nft: Error: Could not process rule: Operation not supported\n synproxy name mysynproxy\n ^^^^^^^^^^^^^^^^^^^^^^^^"}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nnetfilter: nft_objref: validar expresiones objref y objrefmap\n\nHacer referencia a un objeto con estado synproxy desde el hook OUTPUT provoca un fallo del kernel debido a llamadas recursivas infinitas:\n\nERROR: La p\u00e1gina de protecci\u00f3n de la pila de la TAREA fue alcanzada en 000000008bda5b8c (la pila es 000000003ab1c4a5..00000000494d8b12)\n[...]\nTraza de Llamada:\n __find_rr_leaf+0x99/0x230\n fib6_table_lookup+0x13b/0x2d0\n ip6_pol_route+0xa4/0x400\n fib6_rule_lookup+0x156/0x240\n ip6_route_output_flags+0xc6/0x150\n __nf_ip6_route+0x23/0x50\n synproxy_send_tcp_ipv6+0x106/0x200\n synproxy_send_client_synack_ipv6+0x1aa/0x1f0\n nft_synproxy_do_eval+0x263/0x310\n nft_do_chain+0x5a8/0x5f0 [nf_tables\n nft_do_chain_inet+0x98/0x110\n nf_hook_slow+0x43/0xc0\n __ip6_local_out+0xf0/0x170\n ip6_local_out+0x17/0x70\n synproxy_send_tcp_ipv6+0x1a2/0x200\n synproxy_send_client_synack_ipv6+0x1aa/0x1f0\n[...]\n\nImplementar funciones de validaci\u00f3n de expresiones objref y objrefmap.\n\nActualmente, solo el tipo de objeto NFT_OBJECT_SYNPROXY requiere validaci\u00f3n. Esto tambi\u00e9n manejar\u00e1 un salto a una cadena utilizando un objeto synproxy desde el hook OUTPUT.\n\nAhora, al intentar hacer referencia a un objeto synproxy en el hook OUTPUT, nft producir\u00e1 el siguiente error:\n\nsynproxy_crash.nft: Error: No se pudo procesar la regla: Operaci\u00f3n no soportada\n synproxy name mysynproxy\n ^^^^^^^^^^^^^^^^^^^^^^^^"}], "id": "CVE-2025-40206", "lastModified": "2026-10-19T21:10:00.160", "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"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2025-40206", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-10-15T21:58:13.235707Z", "version": "2.0.3"}}]}, "published": "2025-11-12T22:15:47.893", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/0028e0134c64d9ed21728341a74fcfc59cd0f944"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/4c1cf72ec10be5a9ad264650cadffa1fbce6fabd"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/7ea55a44493a5a36c3b3293b88bbe4841f9dbaf0"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/f31bcea12222a26d6f151df9c4a6d21f2eec1724"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/f359b809d54c6e3dd1d039b97e0b68390b0e53e4"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Deferred"}

{"bugzilla": {"description": "kernel: netfilter: nft_objref: validate objref and objrefmap expressions", "id": "2414712", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2414712"}, "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": ["In the Linux kernel, the following vulnerability has been resolved:\nnetfilter: nft_objref: validate objref and objrefmap expressions\nReferencing a synproxy stateful object from OUTPUT hook causes kernel\ncrash due to infinite recursive calls:\nBUG: TASK stack guard page was hit at 000000008bda5b8c (stack is 000000003ab1c4a5..00000000494d8b12)\n[...]\nCall Trace:\n__find_rr_leaf+0x99/0x230\nfib6_table_lookup+0x13b/0x2d0\nip6_pol_route+0xa4/0x400\nfib6_rule_lookup+0x156/0x240\nip6_route_output_flags+0xc6/0x150\n__nf_ip6_route+0x23/0x50\nsynproxy_send_tcp_ipv6+0x106/0x200\nsynproxy_send_client_synack_ipv6+0x1aa/0x1f0\nnft_synproxy_do_eval+0x263/0x310\nnft_do_chain+0x5a8/0x5f0 [nf_tables\nnft_do_chain_inet+0x98/0x110\nnf_hook_slow+0x43/0xc0\n__ip6_local_out+0xf0/0x170\nip6_local_out+0x17/0x70\nsynproxy_send_tcp_ipv6+0x1a2/0x200\nsynproxy_send_client_synack_ipv6+0x1aa/0x1f0\n[...]\nImplement objref and objrefmap expression validate functions.\nCurrently, only NFT_OBJECT_SYNPROXY object type requires validation.\nThis will also handle a jump to a chain using a synproxy object from the\nOUTPUT hook.\nNow when trying to reference a synproxy object in the OUTPUT hook, nft\nwill produce the following error:\nsynproxy_crash.nft: Error: Could not process rule: Operation not supported\nsynproxy name mysynproxy\n^^^^^^^^^^^^^^^^^^^^^^^^"], "name": "CVE-2025-40206", "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": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not 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": "2025-11-12T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2025-40206\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-40206\nhttps://lore.kernel.org/linux-cve-announce/2025111247-CVE-2025-40206-b396@gregkh/T"], "threat_severity": "Moderate"}

{"created": "2025-11-13T09:52:17.714666+00:00", "updated": "2025-11-13T09:52:17.714691+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}