Quick answers
- Is CVE-2026-91998 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-91998 being exploited in the wild.
- How severe is CVE-2026-91998?
- Critical severity, with a CVSS score of 9.9, published 15 September 2026.
- Which products and versions are affected?
- Casdoor Casdoor through 4.4.0.
- Is there a fix for CVE-2026-91998?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-91998 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-91998?
- Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
The vulnerability is an authorization bypass in the /api/mcp endpoint that fails to properly validate whether a requestor has permission to perform administrative actions across organizations. An attacker who possesses a valid clientId and clientSecret from any registered application can authenticate to the endpoint and perform privileged operations (user enumeration, creation of administrator accounts, modification, and deletion of users) on any organization's data. The flaw exists in the authorization logic (authz.go) which does not properly enforce per-organization access controls. No client-side action or additional authentication is required beyond possession of valid application credentials. Patches addressing this authorization bypass are expected in versions after 4.4.0.
Affected products
- Casdoor Casdoor through 4.4.0
Timeline
- 2026-09-15: disclosed