Security advisory

{
  "id": "e157ca6c42b0b4685dd20b88deb73f39ee54eed96c4c84ba1955b9a298d4b63e",
  "url": "https://osv.dev/vulnerability/CVE-2017-11424",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2017-11424",
    "summary": "In PyJWT 1.5.0 and below the `invalid_strings` check in `HMACAlgorithm.prepare_key` does not account for all PEM encoded public keys. Specifically, the PKCS1 PEM encoded format would be allowed because it is prefaced with the string `-----BEGIN RSA PUBLIC KEY-----` which is not accounted for. This enables symmetric/asymmetric key confusion attacks against users using the PKCS1 PEM encoded public keys, which would allow an attacker to craft JWTs from scratch.",
    "evidence": "osv:CVE-2017-11424",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2017-11424",
      "aliases": [
        "CVE-2017-11424",
        "GHSA-r9jw-mwhq-wp62",
        "PYSEC-2017-24"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/jpadilla/pyjwt",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "last_affected": "908ee84aeefb8126a94e48e88ba9916d9d2512b3"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:pyjwt_project:pyjwt:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "last_affected": "1.5.0"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "1.5.0",
            "1.4.2",
            "1.4.1",
            "1.4.0",
            "1.3.0",
            "1.2.0",
            "1.1.0",
            "1.0.1",
            "1.0.0",
            "0.4.3",
            "0.4.2",
            "0.4.1",
            "0.4.0",
            "0.3.2",
            "0.3.1",
            "0.3.0",
            "0.2.3",
            "0.2.2",
            "0.2.0",
            "0.1.9",
            "0.1.6"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2017-11424.json"
          }
        }
      ],
      "modified": "2026-10-20T10:48:01.335372797Z",
      "provider": "osv",
      "references": [
        "https://github.com/jpadilla/pyjwt/pull/277"
      ],
      "provider_metadata": {
        "unresolved_ranges": [
          {
            "cpes": [
              "cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*",
              "cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*"
            ],
            "vendor_product": "debian:debian_linux",
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "8.0"
                  },
                  {
                    "last_affected": "8.0"
                  },
                  {
                    "introduced": "9.0"
                  },
                  {
                    "last_affected": "9.0"
                  }
                ],
                "source": "CPE_STRING"
              }
            ]
          }
        ]
      }
    },
    "related_cves": [
      {
        "value": "CVE-2017-11424",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 379949,
  "published_at": "2017-08-24T16:29:00.197+00:00"
}