{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "versions": [
              {
                "introduced": "0"
              },
              {
                "fixed": "5.9.2"
              }
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "b3f3f3f3df9eae8f665aa3b02ce707c4902c62dc"
            },
            {
              "fixed": "540d4060e877a03ae95343c1a8560a26768585ee"
            }
          ],
          "repo": "https://github.com/servicestack/servicestack",
          "type": "GIT"
        }
      ]
    }
  ],
  "details": "ServiceStack before 5.9.2 mishandles JWT signature verification unless an application has a custom ValidateToken function that establishes a valid minimum length for a signature.",
  "id": "CVE-2020-28042",
  "modified": "2026-03-13T21:50:25.207289506Z",
  "published": "2020-11-02T21:15:31.320Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://forums.servicestack.net/t/servicestack-v5-9-2-released/8850"
    },
    {
      "type": "FIX",
      "url": "https://github.com/ServiceStack/ServiceStack/commit/540d4060e877a03ae95343c1a8560a26768585ee"
    },
    {
      "type": "EVIDENCE",
      "url": "https://www.shielder.it/advisories/servicestack-jwt-signature-verification-bypass/"
    },
    {
      "type": "EVIDENCE",
      "url": "https://www.shielder.it/blog/2020/11/re-discovering-a-jwt-authentication-bypass-in-servicestack/"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    }
  ]
}