Security advisory

{
  "id": "145147aa0463bb0fd472fb9d957b59add87f96c3d8fb37ed6c302211e49a6470",
  "url": "https://osv.dev/vulnerability/CVE-2020-15957",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2020-15957",
    "summary": "An issue was discovered in DP3T-Backend-SDK before 1.1.1 for Decentralised Privacy-Preserving Proximity Tracing (DP3T). When it is configured to check JWT before uploading/publishing keys, it is possible to skip the signature check by providing a JWT token with alg=none.",
    "evidence": "osv:CVE-2020-15957",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2020-15957",
      "aliases": [
        "CVE-2020-15957",
        "GHSA-5m5q-3qw2-3xf3"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/dp-3t/dp3t-sdk-backend",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "b8c6476303097b195f084587d0854997146c79f4"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:dp3t-backend-software_development_kit_project:dp3t-backend-software_development_kit:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "1.1.1"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v1.1.0",
            "v1.0.5",
            "v1.0.4",
            "v1.0.3"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-15957.json"
          }
        }
      ],
      "modified": "2026-10-20T10:51:58.550927371Z",
      "provider": "osv",
      "references": [
        "https://github.com/DP-3T/dp3t-sdk-backend/compare/v1.0.4...v1.1.0",
        "https://github.com/dp-3T/dp3t-sdk-backend",
        "https://github.com/DP-3T/dp3t-sdk-backend/security/advisories/GHSA-5m5q-3qw2-3xf3"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2020-15957",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 383181,
  "published_at": "2020-07-30T14:15:12.26+00:00"
}