{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "versions": [
              {
                "introduced": "0"
              },
              {
                "fixed": "0.5.4"
              }
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "14c4772ee1f9a76c7bae50368884446878d68a68"
            },
            {
              "fixed": "c66fb689d50010662f705d5b585c6388ce555dbd"
            }
          ],
          "repo": "https://github.com/fusionauth/fusionauth-samlv2",
          "type": "GIT"
        }
      ]
    }
  ],
  "details": "FusionAuth fusionauth-samlv2 before 0.5.4 allows XXE attacks via a forged AuthnRequest or LogoutRequest because parseFromBytes uses javax.xml.parsers.DocumentBuilderFactory unsafely.",
  "id": "CVE-2021-27736",
  "modified": "2026-03-13T21:54:19.282511270Z",
  "published": "2021-04-22T14:15:09.123Z",
  "references": [
    {
      "type": "FIX",
      "url": "https://github.com/FusionAuth/fusionauth-samlv2/commit/c66fb689d50010662f705d5b585c6388ce555dbd"
    },
    {
      "type": "FIX",
      "url": "https://github.com/FusionAuth/fusionauth-samlv2/compare/0.5.3...0.5.4"
    },
    {
      "type": "EVIDENCE",
      "url": "https://www.compass-security.com/fileadmin/Research/Advisories/2021-03_CSNC-2021-004_FusionAuth_SAML_Library_XML_External_Entity.txt"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}