Vulnerability · Published Oct 11, 2026 · Assigned by VulnCheck

CVE-2026-108725Cheshire Cat AI core through 2.0.23 Stored XSS via uploads plugin

Medium 5.4

In plain English

A medium-severity cross-site scripting in core from cheshire-cat-ai. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 18% of all known vulnerabilities).

Severity (CVSS 3.1)5.4Medium

Exploit odds (30 days)0.3%top 81.6% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

Cheshire Cat AI core through 2.0.23 contains a stored cross-site scripting vulnerability in the uploads plugin that allows authenticated users to upload HTML files via POST /uploads without type restrictions. Attackers can send the public GET /uploads/{path} URL to a signed-in victim, executing script in the application origin with the victim's access_token cookie, including administrators.

Affected products (as reported)

Vendor	Product	Versions
cheshire-cat-ai	core	0 – through 2.0.23

Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

References

https://hackmd.io/@haind03/cheshire-cat-uploads-stored-html-same-origin-xss third-party-advisory
https://github.com/cheshire-cat-ai/core/blob/c22731e7009ac89835b1d7b1cabc5989d998ec3e/src/cat/scaffold/plugins/uploads/endpoints.py#L28-L96 technical-description
https://github.com/cheshire-cat-ai/core product
VulnCheck Advisory: Cheshire Cat AI core through 2.0.23 Stored XSS via uploads plugin third-party-advisory