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        "cveId": "CVE-2021-47591",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2024-05-24T15:11:00.733Z",
        "datePublished": "2024-06-19T14:53:54.918Z",
        "dateUpdated": "2026-05-11T13:57:30.264Z"
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                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: remove tcp ulp setsockopt support\n\nTCP_ULP setsockopt cannot be used for mptcp because its already\nused internally to plumb subflow (tcp) sockets to the mptcp layer.\n\nsyzbot managed to trigger a crash for mptcp connections that are\nin fallback mode:\n\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]\n tcp_set_ulp+0x428/0x4c0 net/ipv4/tcp_ulp.c:160\n do_tcp_setsockopt+0x455/0x37c0 net/ipv4/tcp.c:3391\n mptcp_setsockopt+0x1b47/0x2400 net/mptcp/sockopt.c:638\n\nRemove support for TCP_ULP setsockopt."
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                    "vendor": "Linux",
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                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
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                            "versionType": "original_commit_for_fix"
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                    "url": "https://git.kernel.org/stable/c/3de0c86d42f841d1d64f316cd949e65c566f0734"
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                    "url": "https://git.kernel.org/stable/c/404cd9a22150f24acf23a8df2ad0c094ba379f57"
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