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{"configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "38A89EC4-168A-4514-A383-6B85436E12DE", "versionEndExcluding": "5.10.88", "versionStartIncluding": "5.6", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "11274E95-438A-449A-B100-01B2B0046669", "versionEndExcluding": "5.15.11", "versionStartIncluding": "5.11", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc1:*:*:*:*:*:*", "matchCriteriaId": "357AA433-37E8-4323-BFB2-3038D6E4B414", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc2:*:*:*:*:*:*", "matchCriteriaId": "A73429BA-C2D9-4D0C-A75F-06A1CA8B3983", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc3:*:*:*:*:*:*", "matchCriteriaId": "F621B5E3-E99D-49E7-90B9-EC3B77C95383", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc4:*:*:*:*:*:*", "matchCriteriaId": "F7BFDCAA-1650-49AA-8462-407DD593F94F", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc5:*:*:*:*:*:*", "matchCriteriaId": "6EC9882F-866D-4ACB-8FBC-213D8D8436C8", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: clear 'kern' flag from fallback sockets\n\nThe mptcp ULP extension relies on sk->sk_sock_kern being set correctly:\nIt prevents setsockopt(fd, IPPROTO_TCP, TCP_ULP, \"mptcp\", 6); from\nworking for plain tcp sockets (any userspace-exposed socket).\n\nBut in case of fallback, accept() can return a plain tcp sk.\nIn such case, sk is still tagged as 'kernel' and setsockopt will work.\n\nThis will crash the kernel, The subflow extension has a NULL ctx->conn\nmptcp socket:\n\nBUG: KASAN: null-ptr-deref in subflow_data_ready+0x181/0x2b0\nCall Trace:\n tcp_data_ready+0xf8/0x370\n [..]"}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: mptcp: borrar el indicador 'kern' de los sockets de reserva La extensi\u00f3n mptcp ULP depende de que sk->sk_sock_kern est\u00e9 configurado correctamente: impide que setsockopt(fd, IPPROTO_TCP, TCP_ULP, \"mptcp\", 6); de funcionar para sockets tcp simples (cualquier socket expuesto al espacio de usuario). Pero en caso de respaldo, aceptar() puede devolver un sk tcp simple. En tal caso, sk todav\u00eda est\u00e1 etiquetado como 'kernel' y setsockopt funcionar\u00e1. Esto bloquear\u00e1 el kernel. La extensi\u00f3n de subflujo tiene un socket NULL ctx->conn mptcp: ERROR: KASAN: null-ptr-deref en subflow_data_ready+0x181/0x2b0 Seguimiento de llamadas: tcp_data_ready+0xf8/0x370 [..]"}], "id": "CVE-2021-47593", "lastModified": "2024-11-21T06:36:37.517", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 5.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}]}, "published": "2024-06-19T15:15:53.890", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/451f1eded7f56e93aaf52eb547ba97742d9c0e97"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/c26ac0ea3a91c210cf90452e625dc441adf3e549"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/d6692b3b97bdc165d150f4c1505751a323a80717"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/451f1eded7f56e93aaf52eb547ba97742d9c0e97"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/c26ac0ea3a91c210cf90452e625dc441adf3e549"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/d6692b3b97bdc165d150f4c1505751a323a80717"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-476"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: mptcp: clear 'kern' flag from fallback sockets", "id": "2293234", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2293234"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-476", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nmptcp: clear 'kern' flag from fallback sockets\nThe mptcp ULP extension relies on sk->sk_sock_kern being set correctly:\nIt prevents setsockopt(fd, IPPROTO_TCP, TCP_ULP, \"mptcp\", 6); from\nworking for plain tcp sockets (any userspace-exposed socket).\nBut in case of fallback, accept() can return a plain tcp sk.\nIn such case, sk is still tagged as 'kernel' and setsockopt will work.\nThis will crash the kernel, The subflow extension has a NULL ctx->conn\nmptcp socket:\nBUG: KASAN: null-ptr-deref in subflow_data_ready+0x181/0x2b0\nCall Trace:\ntcp_data_ready+0xf8/0x370\n[..]"], "name": "CVE-2021-47593", "package_state": [{"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": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2024-06-19T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2021-47593\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-47593\nhttps://lore.kernel.org/linux-cve-announce/2024061919-CVE-2021-47593-a7a7@gregkh/T"], "threat_severity": "Low"}

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