Auth bypass in Cheshire-Cat-Ai Cheshire Cat Ai
CVE-2026-90579
A vulnerability has been found in cheshire-cat-ai Cheshire Cat AI up to 1.9.2. This affects the function _authorize_http_key of the file core/cat/factory/custom_auth_handler.py. The manipulation of the argument user_id leads to missing authentication. The attack may be initiated remotely. The exploit has been disclosed to the public and may be used. The project was informed of the problem early through an issue report but has not responded yet.
Vulnerability class: Broken Authentication
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.3 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L.
EPSS exploit prediction
EPSS: 0.007 (51.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 51st percentile — 51.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: 0.000
Affected products
- Cheshire-Cat-Ai Cheshire Cat Ai — versions 1.9.0, 1.9.1, 1.9.2
Weakness classification (CWE)
References
- github.com/cheshire-cat-ai/core/issues/1137 (issue-tracking, exploit)
- vuldb.com/cve/CVE-2026-90579 (third-party-advisory)
- vuldb.com/submit/913219 (third-party-advisory)
- vuldb.com/vuln/403164 (technical-description, vdb-entry)
- vuldb.com/vuln/403164/cti (signature, permissions-required)
Frequently asked questions
- What is CVE-2026-90579?
- CVE-2026-90579 is a high-severity vulnerability in Cheshire-Cat-Ai Cheshire Cat Ai, classified under Improper Authentication. CVSS score: 7.3/10. Published 2026-09-13.
- How severe is CVE-2026-90579?
- High severity. CVSS v3 base score is 7.3 out of 10.