FKIE_CVE-2021-47591

Vulnerability from fkie_nvd - Published: 2024-06-19 15:15 - Updated: 2026-06-17 04:17
Severity
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: mptcp: remove tcp ulp setsockopt support TCP_ULP setsockopt cannot be used for mptcp because its already used internally to plumb subflow (tcp) sockets to the mptcp layer. syzbot managed to trigger a crash for mptcp connections that are in fallback mode: KASAN: null-ptr-deref in range [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 [inline] [..] __tcp_set_ulp net/ipv4/tcp_ulp.c:139 [inline] 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 Remove support for TCP_ULP setsockopt.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/3de0c86d42f841d1d64f316cd949e65c566f0734Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/404cd9a22150f24acf23a8df2ad0c094ba379f57Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/3de0c86d42f841d1d64f316cd949e65c566f0734Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/404cd9a22150f24acf23a8df2ad0c094ba379f57Patch
Impacted products
Vendor Product Version
linux linux_kernel *
linux linux_kernel 5.16
linux linux_kernel 5.16
linux linux_kernel 5.16
linux linux_kernel 5.16
linux linux_kernel 5.16
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/mptcp/sockopt.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "3de0c86d42f841d1d64f316cd949e65c566f0734",
              "status": "affected",
              "version": "d9e4c129181004ec94b315b0c9db5eeb09da75e6",
              "versionType": "git"
            },
            {
              "lessThan": "404cd9a22150f24acf23a8df2ad0c094ba379f57",
              "status": "affected",
              "version": "d9e4c129181004ec94b315b0c9db5eeb09da75e6",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/mptcp/sockopt.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.13"
            },
            {
              "lessThan": "5.13",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "5.16",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "D42075C1-1BC2-41C8-B06D-3A7E0EDABE84",
              "versionEndExcluding": "5.15.11",
              "versionStartIncluding": "5.13",
              "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"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "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."
    },
    {
      "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": [
      {
        "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"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2021-47591",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2024-09-10T17:12:33.600657Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2024-06-19T15:15:53.700",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/3de0c86d42f841d1d64f316cd949e65c566f0734"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/404cd9a22150f24acf23a8df2ad0c094ba379f57"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/3de0c86d42f841d1d64f316cd949e65c566f0734"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/404cd9a22150f24acf23a8df2ad0c094ba379f57"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-476"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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