Vulnerability-Lookup

GHSA-JVMW-G7RG-X26F

Vulnerability from github – Published: 2026-09-15 12:31 – Updated: 2026-09-15 12:31

Details

Casdoor through 4.4.0 contains an authorization bypass vulnerability in the /api/mcp endpoint that allows attackers with any application's clientId and clientSecret to gain unrestricted access to user administration across all organizations. Attackers can enumerate user records including password salts and email addresses, create administrator accounts, modify existing users, and delete them in any organization by supplying legitimate credentials from a single application.

Severity

9.9 (Critical)


                  
                    CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

9.4 (Critical)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

Show details on source website

JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-91998"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-863"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-15T12:17:55Z",
    "severity": "CRITICAL"
  },
  "details": "Casdoor through 4.4.0 contains an authorization bypass vulnerability in the /api/mcp endpoint that allows attackers with any application\u0027s clientId and clientSecret to gain unrestricted access to user administration across all organizations. Attackers can enumerate user records including password salts and email addresses, create administrator accounts, modify existing users, and delete them in any organization by supplying legitimate credentials from a single application.",
  "id": "GHSA-jvmw-g7rg-x26f",
  "modified": "2026-09-15T12:31:47Z",
  "published": "2026-09-15T12:31:47Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-91998"
    },
    {
      "type": "WEB",
      "url": "https://github.com/casdoor/casdoor"
    },
    {
      "type": "WEB",
      "url": "https://github.com/casdoor/casdoor/blob/v4.4.0/authz/authz.go#L174-L176"
    },
    {
      "type": "WEB",
      "url": "https://github.com/casdoor/casdoor/blob/v4.4.0/mcpself/user.go"
    },
    {
      "type": "WEB",
      "url": "https://github.com/casdoor/casdoor/blob/v4.4.0/routers/base.go#L122-L154"
    },
    {
      "type": "WEB",
      "url": "https://github.com/geo-chen/oss/blob/main/casdoor.md#finding-2-application-credential-authorization-bypass-in-apimcp-enables-unrestricted-cross-organization-user-administration"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/casdoor-through-4.4.0-cross-organization-user-administration-via-api-mcp"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-91998 (GCVE-0-2026-91998)

Vulnerability from cvelistv5 – Published: 2026-09-15 11:35 – Updated: 2026-09-15 11:35

Title

Casdoor through 4.4.0 Cross-Organization User Administration via /api/mcp

Summary

Severity

9.4 (Critical)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

9.9 (Critical)


                        
                          CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

CWE

CWE-863 - Incorrect Authorization

Assigner

VulnCheck mitre root

References

6 references

URL	Tags
https://github.com/geo-chen/oss/blob/main/casdoor…	third-party-advisoryexploit
https://github.com/casdoor/casdoor/blob/v4.4.0/au…	technical-description
https://github.com/casdoor/casdoor/blob/v4.4.0/ro…	technical-description
https://github.com/casdoor/casdoor/blob/v4.4.0/mc…	technical-description
https://github.com/casdoor/casdoor	product
https://www.vulncheck.com/advisories/casdoor-thro…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
casdoor	casdoor	Affected: 0 , ≤ 4.4.0 (semver) cpe:2.3:a:casbin:casdoor::::::::

Date Public

2026-09-13 00:00

Credits

George Chen

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "packageURL": "pkg:github/casdoor/casdoor",
          "product": "casdoor",
          "repo": "https://github.com/casdoor/casdoor",
          "vendor": "casdoor",
          "versions": [
            {
              "lessThanOrEqual": "4.4.0",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:casbin:casdoor:*:*:*:*:*:*:*:*",
                  "versionEndIncluding": "4.4.0",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "reporter",
          "value": "George Chen"
        }
      ],
      "datePublic": "2026-09-13T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "Casdoor through 4.4.0 contains an authorization bypass vulnerability in the /api/mcp endpoint that allows attackers with any application\u0027s clientId and clientSecret to gain unrestricted access to user administration across all organizations. Attackers can enumerate user records including password salts and email addresses, create administrator accounts, modify existing users, and delete them in any organization by supplying legitimate credentials from a single application."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 9.4,
            "baseSeverity": "CRITICAL",
            "privilegesRequired": "LOW",
            "subAvailabilityImpact": "HIGH",
            "subConfidentialityImpact": "HIGH",
            "subIntegrityImpact": "HIGH",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH"
          },
          "format": "CVSS"
        },
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 9.9,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
            "version": "3.1"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-863",
              "description": "Incorrect Authorization",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-15T11:35:52.041Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
      },
      "references": [
        {
          "name": "Researcher write-up, Finding 2",
          "tags": [
            "third-party-advisory",
            "exploit"
          ],
          "url": "https://github.com/geo-chen/oss/blob/main/casdoor.md#finding-2-application-credential-authorization-bypass-in-apimcp-enables-unrestricted-cross-organization-user-administration"
        },
        {
          "name": "authz/authz.go unconditional app allow at v4.4.0",
          "tags": [
            "technical-description"
          ],
          "url": "https://github.com/casdoor/casdoor/blob/v4.4.0/authz/authz.go#L174-L176"
        },
        {
          "name": "getUsernameByClientIdSecret at v4.4.0",
          "tags": [
            "technical-description"
          ],
          "url": "https://github.com/casdoor/casdoor/blob/v4.4.0/routers/base.go#L122-L154"
        },
        {
          "name": "mcpself/user.go unscoped user tools at v4.4.0",
          "tags": [
            "technical-description"
          ],
          "url": "https://github.com/casdoor/casdoor/blob/v4.4.0/mcpself/user.go"
        },
        {
          "tags": [
            "product"
          ],
          "url": "https://github.com/casdoor/casdoor"
        },
        {
          "name": "VulnCheck Advisory: Casdoor through 4.4.0 Cross-Organization User Administration via /api/mcp",
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/casdoor-through-4.4.0-cross-organization-user-administration-via-api-mcp"
        }
      ],
      "title": "Casdoor through 4.4.0 Cross-Organization User Administration via /api/mcp",
      "x_generator": {
        "engine": "vulncheck-endgame"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-91998",
    "datePublished": "2026-09-15T11:35:52.041Z",
    "dateReserved": "2026-09-15T11:11:13.312Z",
    "dateUpdated": "2026-09-15T11:35:52.041Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.