CVE-2026-94613 (GCVE-0-2026-94613)

Vulnerability from cvelistv5 – Published: 2026-09-24 16:13 – Updated: 2026-09-24 16:13
VLAI
Title
authentik: Denial of Service via Document Type Declarations in SAML Messages
Summary
authentik is an open-source identity provider. Prior to 2026.2.7, 2026.5.7, and 2026.8.2, an unauthenticated attacker can submit a malformed SAML message to an authentik deployment using SAML in either the identity-provider or SAML source role. The message can stop the worker handling /application/saml/* or /source/saml/*, causing the requests assigned to that worker to fail. Worker process termination and automatic restart do not destroy database-backed sessions, but continued malicious messages can cause a sustained share of legitimate traffic to fail. Other protocol implementations are not affected. This issue is fixed in versions 2026.2.7, 2026.5.7, and 2026.8.2.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
References
Impacted products
Vendor Product Version CPE status
goauthentik authentik Affected: < 2026.2.7
Affected: >= 2026.5.0, < 2026.5.7
Affected: >= 2026.8.0, < 2026.8.2
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{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "authentik",
          "vendor": "goauthentik",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 2026.2.7"
            },
            {
              "status": "affected",
              "version": "\u003e= 2026.5.0, \u003c 2026.5.7"
            },
            {
              "status": "affected",
              "version": "\u003e= 2026.8.0, \u003c 2026.8.2"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "authentik is an open-source identity provider. Prior to 2026.2.7, 2026.5.7, and 2026.8.2, an unauthenticated attacker can submit a malformed SAML message to an authentik deployment using SAML in either the identity-provider or SAML source role. The message can stop the worker handling /application/saml/* or /source/saml/*, causing the requests assigned to that worker to fail. Worker process termination and automatic restart do not destroy database-backed sessions, but continued malicious messages can cause a sustained share of legitimate traffic to fail. Other protocol implementations are not affected. This issue is fixed in versions 2026.2.7, 2026.5.7, and 2026.8.2."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-770",
              "description": "CWE-770: Allocation of Resources Without Limits or Throttling",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-24T16:13:17.785Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/goauthentik/authentik/security/advisories/GHSA-cxwx-9x59-28qm",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/goauthentik/authentik/security/advisories/GHSA-cxwx-9x59-28qm"
        },
        {
          "name": "https://github.com/goauthentik/authentik/pull/25959",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/goauthentik/authentik/pull/25959"
        },
        {
          "name": "https://github.com/goauthentik/authentik/pull/25964",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/goauthentik/authentik/pull/25964"
        },
        {
          "name": "https://github.com/goauthentik/authentik/pull/25969",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/goauthentik/authentik/pull/25969"
        },
        {
          "name": "https://github.com/goauthentik/authentik/pull/25974",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/goauthentik/authentik/pull/25974"
        },
        {
          "name": "https://github.com/goauthentik/authentik/commit/03d19d63b8d8dd7bc3de7cf6e57c6df341a9fc86",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/goauthentik/authentik/commit/03d19d63b8d8dd7bc3de7cf6e57c6df341a9fc86"
        },
        {
          "name": "https://github.com/goauthentik/authentik/commit/4cf2f803b1c2ef38c224eead375fd057a10ee8ac",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/goauthentik/authentik/commit/4cf2f803b1c2ef38c224eead375fd057a10ee8ac"
        },
        {
          "name": "https://github.com/goauthentik/authentik/commit/732adad26bb97361b6bf25ef138df5c16471ba1f",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/goauthentik/authentik/commit/732adad26bb97361b6bf25ef138df5c16471ba1f"
        },
        {
          "name": "https://github.com/goauthentik/authentik/commit/a029f5372295bfeb1e334855f78601681cdc9a2d",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/goauthentik/authentik/commit/a029f5372295bfeb1e334855f78601681cdc9a2d"
        },
        {
          "name": "https://docs.goauthentik.io/releases/2026.2#fixed-in-202627",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://docs.goauthentik.io/releases/2026.2#fixed-in-202627"
        },
        {
          "name": "https://docs.goauthentik.io/releases/2026.5#fixed-in-202657",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://docs.goauthentik.io/releases/2026.5#fixed-in-202657"
        },
        {
          "name": "https://docs.goauthentik.io/releases/2026.8#fixed-in-202682",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://docs.goauthentik.io/releases/2026.8#fixed-in-202682"
        },
        {
          "name": "https://github.com/goauthentik/authentik/releases/tag/version/2026.2.7",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/goauthentik/authentik/releases/tag/version/2026.2.7"
        },
        {
          "name": "https://github.com/goauthentik/authentik/releases/tag/version/2026.5.7",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/goauthentik/authentik/releases/tag/version/2026.5.7"
        },
        {
          "name": "https://github.com/goauthentik/authentik/releases/tag/version/2026.8.2",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/goauthentik/authentik/releases/tag/version/2026.8.2"
        }
      ],
      "source": {
        "advisory": "GHSA-cxwx-9x59-28qm",
        "discovery": "UNKNOWN"
      },
      "title": "authentik: Denial of Service via Document Type Declarations in SAML Messages"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-94613",
    "datePublished": "2026-09-24T16:13:17.785Z",
    "dateReserved": "2026-09-21T21:32:23.741Z",
    "dateUpdated": "2026-09-24T16:13:17.785Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "product": "authentik",
                "vendor": "goauthentik",
                "versions": [
                  {
                    "status": "affected",
                    "version": "\u003c 2026.2.7"
                  },
                  {
                    "status": "affected",
                    "version": "\u003e= 2026.5.0, \u003c 2026.5.7"
                  },
                  {
                    "status": "affected",
                    "version": "\u003e= 2026.8.0, \u003c 2026.8.2"
                  }
                ]
              }
            ],
            "source": "security-advisories@github.com"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "authentik is an open-source identity provider. Prior to 2026.2.7, 2026.5.7, and 2026.8.2, an unauthenticated attacker can submit a malformed SAML message to an authentik deployment using SAML in either the identity-provider or SAML source role. The message can stop the worker handling /application/saml/* or /source/saml/*, causing the requests assigned to that worker to fail. Worker process termination and automatic restart do not destroy database-backed sessions, but continued malicious messages can cause a sustained share of legitimate traffic to fail. Other protocol implementations are not affected. This issue is fixed in versions 2026.2.7, 2026.5.7, and 2026.8.2."
          }
        ],
        "id": "CVE-2026-94613",
        "lastModified": "2026-09-24T17:17:17.723",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 7.5,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 3.9,
              "impactScore": 3.6,
              "source": "security-advisories@github.com",
              "type": "Secondary"
            }
          ]
        },
        "published": "2026-09-24T17:17:17.723",
        "references": [
          {
            "source": "security-advisories@github.com",
            "url": "https://docs.goauthentik.io/releases/2026.2#fixed-in-202627"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://docs.goauthentik.io/releases/2026.5#fixed-in-202657"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://docs.goauthentik.io/releases/2026.8#fixed-in-202682"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/goauthentik/authentik/commit/03d19d63b8d8dd7bc3de7cf6e57c6df341a9fc86"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/goauthentik/authentik/commit/4cf2f803b1c2ef38c224eead375fd057a10ee8ac"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/goauthentik/authentik/commit/732adad26bb97361b6bf25ef138df5c16471ba1f"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/goauthentik/authentik/commit/a029f5372295bfeb1e334855f78601681cdc9a2d"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/goauthentik/authentik/pull/25959"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/goauthentik/authentik/pull/25964"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/goauthentik/authentik/pull/25969"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/goauthentik/authentik/pull/25974"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/goauthentik/authentik/releases/tag/version/2026.2.7"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/goauthentik/authentik/releases/tag/version/2026.5.7"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/goauthentik/authentik/releases/tag/version/2026.8.2"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/goauthentik/authentik/security/advisories/GHSA-cxwx-9x59-28qm"
          }
        ],
        "sourceIdentifier": "security-advisories@github.com",
        "vulnStatus": "Received",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-770"
              }
            ],
            "source": "security-advisories@github.com",
            "type": "Primary"
          }
        ]
      }
    }
  }
}



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