CVE-2021-47591

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support for TCP_ULP setsockopt."}, {"lang": "es", "value": "En el kernel de Linux, se resolvi\u00f3 la siguiente vulnerabilidad: mptcp: elimina el soporte de tcp ulp setsockopt TCP_ULP setsockopt no se puede usar para mptcp porque ya se usa internamente para conectar sockets de subflujo (tcp) a la capa mptcp. syzbot logr\u00f3 desencadenar un bloqueo para las conexiones mptcp que est\u00e1n en modo alternativo: KASAN: null-ptr-deref en el rango [0x0000000000000020-0x0000000000000027] CPU: 1 PID: 1083 Comm: syz-executor.3 Not tainted 5.16.0-rc2- syzkaller #0 RIP: 0010:tls_build_proto net/tls/tls_main.c:776 [en l\u00ednea] [..] __tcp_set_ulp net/ipv4/tcp_ulp.c:139 [en l\u00ednea] tcp_set_ulp+0x428/0x4c0 net/ipv4/tcp_ulp.c: 160 do_tcp_setsockopt+0x455/0x37c0 net/ipv4/tcp.c:3391 mptcp_setsockopt+0x1b47/0x2400 net/mptcp/sockopt.c:638 Elimina la compatibilidad con TCP_ULP setsockopt."}], "id": "CVE-2021-47591", "lastModified": "2026-06-17T04:17:49.870", "metrics": {"cvssMetricV31": 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{"bugzilla": {"description": "kernel: mptcp: remove tcp ulp setsockopt support", "id": "2293236", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2293236"}, "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: remove tcp ulp setsockopt support\nTCP_ULP setsockopt cannot be used for mptcp because its already\nused internally to plumb subflow (tcp) sockets to the mptcp layer.\nsyzbot managed to trigger a crash for mptcp connections that are\nin fallback mode:\nKASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027]\nCPU: 1 PID: 1083 Comm: syz-executor.3 Not tainted 5.16.0-rc2-syzkaller #0\nRIP: 0010:tls_build_proto net/tls/tls_main.c:776 [inline]\n[..]\n__tcp_set_ulp net/ipv4/tcp_ulp.c:139 [inline]\ntcp_set_ulp+0x428/0x4c0 net/ipv4/tcp_ulp.c:160\ndo_tcp_setsockopt+0x455/0x37c0 net/ipv4/tcp.c:3391\nmptcp_setsockopt+0x1b47/0x2400 net/mptcp/sockopt.c:638\nRemove support for TCP_ULP setsockopt."], "name": "CVE-2021-47591", "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": "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": "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-2021-47591\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-47591\nhttps://lore.kernel.org/linux-cve-announce/2024061919-CVE-2021-47591-955a@gregkh/T"], "threat_severity": "Low"}

{}