Security advisory

{
  "id": "4569b812c38f85a5f972ceb9b039b04c385543ed80591982efb44c1e1c32c3f9",
  "url": "https://osv.dev/vulnerability/CVE-2021-41106",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2021-41106",
    "summary": "JWT is a library to work with JSON Web Token and JSON Web Signature. Prior to versions 3.4.6, 4.0.4, and 4.1.5, users of HMAC-based algorithms (HS256, HS384, and HS512) combined with `Lcobucci\\JWT\\Signer\\Key\\LocalFileReference` as key are having their tokens issued/validated using the file path as hashing key - instead of the contents. The HMAC hashing functions take any string as input and, since users can issue and validate tokens, users are lead to believe that everything works properly. Versions 3.4.6, 4.0.4, and 4.1.5 have been patched to always load the file contents, deprecated the `Lcobucci\\JWT\\Signer\\Key\\LocalFileReference`, and suggest `Lcobucci\\JWT\\Signer\\Key\\InMemory` as the alternative. As a workaround, use `Lcobucci\\JWT\\Signer\\Key\\InMemory` instead of `Lcobucci\\JWT\\Signer\\Key\\LocalFileReference` to create the instances of one's keys.",
    "evidence": "osv:CVE-2021-41106",
    "products": [],
    "severity": "low",
    "structured": {
      "id": "CVE-2021-41106",
      "aliases": [
        "CVE-2021-41106",
        "GHSA-7322-jrq4-x5hf"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/lcobucci/jwt",
              "type": "GIT",
              "events": [
                {
                  "introduced": "320b9f05741b24acbbaf1106ed267ff3817fd74d"
                },
                {
                  "fixed": "3ef8657a78278dfeae7707d51747251db4176240"
                },
                {
                  "introduced": "6d8665ccd924dc076a9b65d1ea8abe21d68f6958"
                },
                {
                  "fixed": "55564265fddf810504110bd68ca311932324b0e9"
                },
                {
                  "introduced": "2f533837091d0b76a89a059e7ed2b2732b2f459e"
                },
                {
                  "fixed": "fe2d89f2eaa7087af4aa166c6f480ef04e000582"
                },
                {
                  "fixed": "8175de5b841fbe3fd97d2d49b3fc15c4ecb39a73"
                },
                {
                  "fixed": "c45bb8b961a8e742d8f6b88ef5ff1bd5cca5d01c"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:lcobucci:jwt:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "3.4.0"
                      },
                      {
                        "fixed": "3.4.6"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:lcobucci:jwt:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "4.0.0"
                      },
                      {
                        "fixed": "4.0.4"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:lcobucci:jwt:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "4.1.0"
                      },
                      {
                        "fixed": "4.1.5"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "range": [
                      {
                        "fixed": "8175de5b841fbe3fd97d2d49b3fc15c4ecb39a73"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "c45bb8b961a8e742d8f6b88ef5ff1bd5cca5d01c"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "versions": [
            "4.1.4",
            "3.4.5",
            "4.0.3",
            "4.1.3",
            "4.0.2",
            "4.1.2",
            "4.1.1",
            "3.4.4",
            "4.1.0",
            "4.0.1",
            "3.4.3",
            "4.0.0",
            "3.4.2",
            "3.4.1",
            "3.4.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-41106.json"
          }
        }
      ],
      "modified": "2026-10-20T10:54:58.416315949Z",
      "provider": "osv",
      "references": [
        "https://github.com/lcobucci/jwt/commit/8175de5b841fbe3fd97d2d49b3fc15c4ecb39a73",
        "https://github.com/lcobucci/jwt/commit/c45bb8b961a8e742d8f6b88ef5ff1bd5cca5d01c",
        "https://github.com/lcobucci/jwt/security/advisories/GHSA-7322-jrq4-x5hf"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2021-41106",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 386598,
  "published_at": "2021-09-28T21:15:07.37+00:00"
}