{
   affected: [
      {
         package: {
            ecosystem: "PyPI",
            name: "fastapi",
         },
         ranges: [
            {
               events: [
                  {
                     introduced: "0",
                  },
                  {
                     fixed: "0.65.2",
                  },
               ],
               type: "ECOSYSTEM",
            },
         ],
      },
   ],
   aliases: [
      "CVE-2021-32677",
   ],
   database_specific: {
      cwe_ids: [
         "CWE-352",
      ],
      github_reviewed: true,
      github_reviewed_at: "2021-06-09T13:34:54Z",
      nvd_published_at: "2021-06-09T18:15:00Z",
      severity: "HIGH",
   },
   details: "### Impact\n\nFastAPI versions lower than `0.65.2` that used cookies for authentication in path operations that received JSON payloads sent by browsers were vulnerable to a Cross-Site Request Forgery (CSRF) attack.\n\nIn versions lower than `0.65.2`, FastAPI would try to read the request payload as JSON even if the `content-type` header sent was not set to `application/json` or a compatible JSON media type (e.g. `application/geo+json`).\n\nSo, a request with a content type of `text/plain` containing JSON data would be accepted and the JSON data would be extracted.\n\nBut requests with content type `text/plain` are exempt from [CORS](https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS) preflights, for being considered [Simple requests](https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS#simple_requests). So, the browser would execute them right away including cookies, and the text content could be a JSON string that would be parsed and accepted by the FastAPI application.\n\n### Patches\n\nThis is fixed in FastAPI `0.65.2`.\n\nThe request data is now parsed as JSON only if the `content-type` header is `application/json` or another JSON compatible media type like `application/geo+json`.\n\n### Workarounds\n\nIt's best to upgrade to the latest FastAPI.\n\nBut still, it would be possible to add a middleware or a dependency that checks the `content-type` header and aborts the request if it is not `application/json` or another JSON compatible content type.\n\n### References\n\n* [CORS on Mozilla web docs](https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS)\n* [This answer on StackExchange](https://security.stackexchange.com/questions/157528/ways-to-bypass-browsers-cors-policy/157531#157531)\n* [OWASP CSRF](https://owasp.org/www-community/attacks/csrf)\n* Fixed in PR [#2118](https://github.com/tiangolo/fastapi/pull/2118)\n\n### For more information\n\nIf you have any questions or comments, write to [security@tiangolo.com](mailto:security@tiangolo.com)",
   id: "GHSA-8h2j-cgx8-6xv7",
   modified: "2024-09-20T17:18:26Z",
   published: "2021-06-10T15:43:54Z",
   references: [
      {
         type: "WEB",
         url: "https://github.com/tiangolo/fastapi/security/advisories/GHSA-8h2j-cgx8-6xv7",
      },
      {
         type: "ADVISORY",
         url: "https://nvd.nist.gov/vuln/detail/CVE-2021-32677",
      },
      {
         type: "WEB",
         url: "https://github.com/tiangolo/fastapi/commit/fa7e3c996edf2d5482fff8f9d890ac2390dede4d",
      },
      {
         type: "WEB",
         url: "https://github.com/pypa/advisory-database/tree/main/vulns/fastapi/PYSEC-2021-100.yaml",
      },
      {
         type: "PACKAGE",
         url: "https://github.com/tiangolo/fastapi",
      },
      {
         type: "WEB",
         url: "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/MATAWX25TYKNEKLDMKWNLYDB34UWTROA",
      },
   ],
   schema_version: "1.4.0",
   severity: [
      {
         score: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N",
         type: "CVSS_V3",
      },
      {
         score: "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N",
         type: "CVSS_V4",
      },
   ],
   summary: "Cross-Site Request Forgery (CSRF) in FastAPI",
}

{
   containers: {
      adp: [
         {
            providerMetadata: {
               dateUpdated: "2024-08-03T23:25:31.094Z",
               orgId: "af854a3a-2127-422b-91ae-364da2661108",
               shortName: "CVE",
            },
            references: [
               {
                  tags: [
                     "x_refsource_CONFIRM",
                     "x_transferred",
                  ],
                  url: "https://github.com/tiangolo/fastapi/security/advisories/GHSA-8h2j-cgx8-6xv7",
               },
               {
                  tags: [
                     "x_refsource_MISC",
                     "x_transferred",
                  ],
                  url: "https://github.com/tiangolo/fastapi/commit/fa7e3c996edf2d5482fff8f9d890ac2390dede4d",
               },
               {
                  name: "FEDORA-2021-917e89c036",
                  tags: [
                     "vendor-advisory",
                     "x_refsource_FEDORA",
                     "x_transferred",
                  ],
                  url: "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MATAWX25TYKNEKLDMKWNLYDB34UWTROA/",
               },
            ],
            title: "CVE Program Container",
         },
      ],
      cna: {
         affected: [
            {
               product: "fastapi",
               vendor: "tiangolo",
               versions: [
                  {
                     status: "affected",
                     version: "< 0.65.2",
                  },
               ],
            },
         ],
         descriptions: [
            {
               lang: "en",
               value: "FastAPI is a web framework for building APIs with Python 3.6+ based on standard Python type hints. FastAPI versions lower than 0.65.2 that used cookies for authentication in path operations that received JSON payloads sent by browsers were vulnerable to a Cross-Site Request Forgery (CSRF) attack. In versions lower than 0.65.2, FastAPI would try to read the request payload as JSON even if the content-type header sent was not set to application/json or a compatible JSON media type (e.g. application/geo+json). A request with a content type of text/plain containing JSON data would be accepted and the JSON data would be extracted. Requests with content type text/plain are exempt from CORS preflights, for being considered Simple requests. The browser will execute them right away including cookies, and the text content could be a JSON string that would be parsed and accepted by the FastAPI application. This is fixed in FastAPI 0.65.2. The request data is now parsed as JSON only if the content-type header is application/json or another JSON compatible media type like application/geo+json. It's best to upgrade to the latest FastAPI, but if updating is not possible then a middleware or a dependency that checks the content-type header and aborts the request if it is not application/json or another JSON compatible content type can act as a mitigating workaround.",
            },
         ],
         metrics: [
            {
               cvssV3_1: {
                  attackComplexity: "LOW",
                  attackVector: "NETWORK",
                  availabilityImpact: "NONE",
                  baseScore: 8.2,
                  baseSeverity: "HIGH",
                  confidentialityImpact: "LOW",
                  integrityImpact: "HIGH",
                  privilegesRequired: "NONE",
                  scope: "UNCHANGED",
                  userInteraction: "NONE",
                  vectorString: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N",
                  version: "3.1",
               },
            },
         ],
         problemTypes: [
            {
               descriptions: [
                  {
                     cweId: "CWE-352",
                     description: "CWE-352: Cross-Site Request Forgery (CSRF)",
                     lang: "en",
                     type: "CWE",
                  },
               ],
            },
         ],
         providerMetadata: {
            dateUpdated: "2021-06-18T02:06:14",
            orgId: "a0819718-46f1-4df5-94e2-005712e83aaa",
            shortName: "GitHub_M",
         },
         references: [
            {
               tags: [
                  "x_refsource_CONFIRM",
               ],
               url: "https://github.com/tiangolo/fastapi/security/advisories/GHSA-8h2j-cgx8-6xv7",
            },
            {
               tags: [
                  "x_refsource_MISC",
               ],
               url: "https://github.com/tiangolo/fastapi/commit/fa7e3c996edf2d5482fff8f9d890ac2390dede4d",
            },
            {
               name: "FEDORA-2021-917e89c036",
               tags: [
                  "vendor-advisory",
                  "x_refsource_FEDORA",
               ],
               url: "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MATAWX25TYKNEKLDMKWNLYDB34UWTROA/",
            },
         ],
         source: {
            advisory: "GHSA-8h2j-cgx8-6xv7",
            discovery: "UNKNOWN",
         },
         title: "Cross-Site Request Forgery (CSRF) in FastAPI",
         x_legacyV4Record: {
            CVE_data_meta: {
               ASSIGNER: "security-advisories@github.com",
               ID: "CVE-2021-32677",
               STATE: "PUBLIC",
               TITLE: "Cross-Site Request Forgery (CSRF) in FastAPI",
            },
            affects: {
               vendor: {
                  vendor_data: [
                     {
                        product: {
                           product_data: [
                              {
                                 product_name: "fastapi",
                                 version: {
                                    version_data: [
                                       {
                                          version_value: "< 0.65.2",
                                       },
                                    ],
                                 },
                              },
                           ],
                        },
                        vendor_name: "tiangolo",
                     },
                  ],
               },
            },
            data_format: "MITRE",
            data_type: "CVE",
            data_version: "4.0",
            description: {
               description_data: [
                  {
                     lang: "eng",
                     value: "FastAPI is a web framework for building APIs with Python 3.6+ based on standard Python type hints. FastAPI versions lower than 0.65.2 that used cookies for authentication in path operations that received JSON payloads sent by browsers were vulnerable to a Cross-Site Request Forgery (CSRF) attack. In versions lower than 0.65.2, FastAPI would try to read the request payload as JSON even if the content-type header sent was not set to application/json or a compatible JSON media type (e.g. application/geo+json). A request with a content type of text/plain containing JSON data would be accepted and the JSON data would be extracted. Requests with content type text/plain are exempt from CORS preflights, for being considered Simple requests. The browser will execute them right away including cookies, and the text content could be a JSON string that would be parsed and accepted by the FastAPI application. This is fixed in FastAPI 0.65.2. The request data is now parsed as JSON only if the content-type header is application/json or another JSON compatible media type like application/geo+json. It's best to upgrade to the latest FastAPI, but if updating is not possible then a middleware or a dependency that checks the content-type header and aborts the request if it is not application/json or another JSON compatible content type can act as a mitigating workaround.",
                  },
               ],
            },
            impact: {
               cvss: {
                  attackComplexity: "LOW",
                  attackVector: "NETWORK",
                  availabilityImpact: "NONE",
                  baseScore: 8.2,
                  baseSeverity: "HIGH",
                  confidentialityImpact: "LOW",
                  integrityImpact: "HIGH",
                  privilegesRequired: "NONE",
                  scope: "UNCHANGED",
                  userInteraction: "NONE",
                  vectorString: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N",
                  version: "3.1",
               },
            },
            problemtype: {
               problemtype_data: [
                  {
                     description: [
                        {
                           lang: "eng",
                           value: "CWE-352: Cross-Site Request Forgery (CSRF)",
                        },
                     ],
                  },
               ],
            },
            references: {
               reference_data: [
                  {
                     name: "https://github.com/tiangolo/fastapi/security/advisories/GHSA-8h2j-cgx8-6xv7",
                     refsource: "CONFIRM",
                     url: "https://github.com/tiangolo/fastapi/security/advisories/GHSA-8h2j-cgx8-6xv7",
                  },
                  {
                     name: "https://github.com/tiangolo/fastapi/commit/fa7e3c996edf2d5482fff8f9d890ac2390dede4d",
                     refsource: "MISC",
                     url: "https://github.com/tiangolo/fastapi/commit/fa7e3c996edf2d5482fff8f9d890ac2390dede4d",
                  },
                  {
                     name: "FEDORA-2021-917e89c036",
                     refsource: "FEDORA",
                     url: "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/MATAWX25TYKNEKLDMKWNLYDB34UWTROA/",
                  },
               ],
            },
            source: {
               advisory: "GHSA-8h2j-cgx8-6xv7",
               discovery: "UNKNOWN",
            },
         },
      },
   },
   cveMetadata: {
      assignerOrgId: "a0819718-46f1-4df5-94e2-005712e83aaa",
      assignerShortName: "GitHub_M",
      cveId: "CVE-2021-32677",
      datePublished: "2021-06-09T17:30:12",
      dateReserved: "2021-05-12T00:00:00",
      dateUpdated: "2024-08-03T23:25:31.094Z",
      state: "PUBLISHED",
   },
   dataType: "CVE_RECORD",
   dataVersion: "5.1",
}