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FKIE_CVE-2021-47496

Vulnerability from fkie_nvd - Published: 2024-05-22 09:15 - Updated: 2026-08-04 10:17
Severity
9.8 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: net/tls: Fix flipped sign in tls_err_abort() calls sk->sk_err appears to expect a positive value, a convention that ktls doesn't always follow and that leads to memory corruption in other code. For instance, [kworker] tls_encrypt_done(..., err=<negative error from crypto request>) tls_err_abort(.., err) sk->sk_err = err; [task] splice_from_pipe_feed ... tls_sw_do_sendpage if (sk->sk_err) { ret = -sk->sk_err; // ret is positive splice_from_pipe_feed (continued) ret = actor(...) // ret is still positive and interpreted as bytes // written, resulting in underflow of buf->len and // sd->len, leading to huge buf->offset and bogus // addresses computed in later calls to actor() Fix all tls_err_abort() callers to pass a negative error code consistently and centralize the error-prone sign flip there, throwing in a warning to catch future misuse and uninlining the function so it really does only warn once.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/da353fac65fede6b8b4cfe207f0d9408e3121105Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/e0cfd5159f314d6b304d030363650b06a2299cbbPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/e41473543f75f7dbc5d605007e6f883f1bd13b9aPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/f3dec7e7ace38224f82cf83f0049159d067c2e19Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/da353fac65fede6b8b4cfe207f0d9408e3121105Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/e0cfd5159f314d6b304d030363650b06a2299cbbPatch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/e41473543f75f7dbc5d605007e6f883f1bd13b9aPatch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/f3dec7e7ace38224f82cf83f0049159d067c2e19Patch
Impacted products
Vendor Product Version
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel 5.15
linux linux_kernel 5.15
linux linux_kernel 5.15
linux linux_kernel 5.15
linux linux_kernel 5.15
linux linux_kernel 5.15
linux linux_kernel 5.15
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "include/net/tls.h",
            "net/tls/tls_sw.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "e0cfd5159f314d6b304d030363650b06a2299cbb",
              "status": "affected",
              "version": "c46234ebb4d1eee5e09819f49169e51cfc6eb909",
              "versionType": "git"
            },
            {
              "lessThan": "f3dec7e7ace38224f82cf83f0049159d067c2e19",
              "status": "affected",
              "version": "c46234ebb4d1eee5e09819f49169e51cfc6eb909",
              "versionType": "git"
            },
            {
              "lessThan": "e41473543f75f7dbc5d605007e6f883f1bd13b9a",
              "status": "affected",
              "version": "c46234ebb4d1eee5e09819f49169e51cfc6eb909",
              "versionType": "git"
            },
            {
              "lessThan": "da353fac65fede6b8b4cfe207f0d9408e3121105",
              "status": "affected",
              "version": "c46234ebb4d1eee5e09819f49169e51cfc6eb909",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "include/net/tls.h",
            "net/tls/tls_sw.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.17"
            },
            {
              "lessThan": "4.17",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.4.*",
              "status": "unaffected",
              "version": "5.4.157",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.77",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.14.*",
              "status": "unaffected",
              "version": "5.14.16",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "5.15",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "965296D4-AA37-4DB2-9ED7-71310E9A6C11",
              "versionEndExcluding": "5.4.157",
              "versionStartIncluding": "4.17",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "26EB7ED9-AEA3-4829-8B5E-08571262F72A",
              "versionEndExcluding": "5.10.77",
              "versionStartIncluding": "5.5",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "2681B950-4548-4649-A9E1-4124B59FC09C",
              "versionEndExcluding": "5.14.16",
              "versionStartIncluding": "5.11",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:5.15:rc1:*:*:*:*:*:*",
              "matchCriteriaId": "E46C74C6-B76B-4C94-A6A4-FD2FFF62D644",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:5.15:rc2:*:*:*:*:*:*",
              "matchCriteriaId": "60134C3A-06E4-48C1-B04F-2903732A4E56",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:5.15:rc3:*:*:*:*:*:*",
              "matchCriteriaId": "0460DA88-8FE1-46A2-9DDA-1F1ABA552E71",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:5.15:rc4:*:*:*:*:*:*",
              "matchCriteriaId": "AF55383D-4DF2-45DC-93F7-571F4F978EAB",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:5.15:rc5:*:*:*:*:*:*",
              "matchCriteriaId": "9E9481B2-8AA6-4CBD-B5D3-C10F51FF6D01",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:5.15:rc6:*:*:*:*:*:*",
              "matchCriteriaId": "EBD45831-4B79-42BC-ABC0-86870F0DEA89",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:5.15:rc7:*:*:*:*:*:*",
              "matchCriteriaId": "948A6B8D-1B72-4945-8680-354E53BE1C80",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/tls: Fix flipped sign in tls_err_abort() calls\n\nsk-\u003esk_err appears to expect a positive value, a convention that ktls\ndoesn\u0027t always follow and that leads to memory corruption in other code.\nFor instance,\n\n    [kworker]\n    tls_encrypt_done(..., err=\u003cnegative error from crypto request\u003e)\n      tls_err_abort(.., err)\n        sk-\u003esk_err = err;\n\n    [task]\n    splice_from_pipe_feed\n      ...\n        tls_sw_do_sendpage\n          if (sk-\u003esk_err) {\n            ret = -sk-\u003esk_err;  // ret is positive\n\n    splice_from_pipe_feed (continued)\n      ret = actor(...)  // ret is still positive and interpreted as bytes\n                        // written, resulting in underflow of buf-\u003elen and\n                        // sd-\u003elen, leading to huge buf-\u003eoffset and bogus\n                        // addresses computed in later calls to actor()\n\nFix all tls_err_abort() callers to pass a negative error code\nconsistently and centralize the error-prone sign flip there, throwing in\na warning to catch future misuse and uninlining the function so it\nreally does only warn once."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: net/tls: corrige las llamadas invertidas de tls_err_abort() sk-\u0026gt;sk_err parece esperar un valor positivo, una convenci\u00f3n que ktls no siempre sigue y que conduce a da\u00f1os en la memoria en otro c\u00f3digo. Por ejemplo, [kworker] tls_encrypt_done(..., err=) tls_err_abort(.., err) sk-\u0026gt;sk_err = err; [tarea] splice_from_pipe_feed ... tls_sw_do_sendpage if (sk-\u0026gt;sk_err) { ret = -sk-\u0026gt;sk_err; // ret es positivo splice_from_pipe_feed (continuaci\u00f3n) ret = actor(...) // ret sigue siendo positivo y se interpreta como bytes // escritos, lo que resulta en un desbordamiento insuficiente de buf-\u0026gt;len y // sd-\u0026gt;len, lo que genera enormes buf-\u0026gt;offset y bogus // direcciones calculadas en llamadas posteriores a actor(). Repare todas las llamadas tls_err_abort() para que pasen un c\u00f3digo de error negativo de manera consistente y centralice el cambio de se\u00f1al propenso a errores all\u00ed, lanzando una advertencia para detectar futuros usos indebidos y eliminaci\u00f3n de l\u00edneas. la funci\u00f3n por lo que realmente solo advierte una vez."
    }
  ],
  "id": "CVE-2021-47496",
  "lastModified": "2026-08-04T10:17:05.910",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 9.8,
          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.9,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      },
      {
        "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": "nvd@nist.gov",
        "type": "Primary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2021-47496",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2024-09-10T15:35:52.280096Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2024-05-22T09:15:11.447",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/da353fac65fede6b8b4cfe207f0d9408e3121105"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/e0cfd5159f314d6b304d030363650b06a2299cbb"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/e41473543f75f7dbc5d605007e6f883f1bd13b9a"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/f3dec7e7ace38224f82cf83f0049159d067c2e19"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/da353fac65fede6b8b4cfe207f0d9408e3121105"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/e0cfd5159f314d6b304d030363650b06a2299cbb"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/e41473543f75f7dbc5d605007e6f883f1bd13b9a"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/f3dec7e7ace38224f82cf83f0049159d067c2e19"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-787"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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