GitHub Advisoryadvisory · PyPI
GHSA-f3q6-69f3-vwch FastChat has a Content Moderation Bypass via Arena Side-by-Side Views
MEDIUM
Official page ↗
- Aliases
- CVE-2026-6608
- Ecosystem
- PyPI
- Packages
- fschat
- Severity
- Moderate
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
- Weaknesses
- CWE-670
- Reviewed
- 2026-04-23
Affected packages
• PyPI fschat: <= 0.2.36 (no fix yet)
Description
A vulnerability was detected in lm-sys fastchat up to 0.2.36. Impacted is the function add_text of the component Arena Side-by-Side View Handler. The manipulation results in incorrect control flow. The attack can be launched remotely. The exploit is now public and may be used. The root cause was fixed in commit 34eca62 for gradio_block_arena_named.py, but three other files were missed.
Related
Alias · CVE (1)
- CVE-2026-6608 A vulnerability was detected in lm-sys fastchat up to 0.2.36. vulnerability
Weakness · CWE (1)
- CWE-670 Always-Incorrect Control Flow Implementation weakness
References
- https://nvd.nist.gov/vuln/detail/CVE-2026-6608 advisory
- https://github.com/lm-sys/FastChat/issues/3834 web
- https://gist.github.com/YLChen-007/e45039d23e698222d887ee09735d9d36 web
- https://github.com/lm-sys/FastChat package
- https://vuldb.com/submit/792228 web
- https://vuldb.com/vuln/358243 web
- https://vuldb.com/vuln/358243/cti web