GitHub Advisoryadvisory · PyPI

GHSA-f3q6-69f3-vwch FastChat has a Content Moderation Bypass via Arena Side-by-Side Views

MEDIUM Published 2026-04-20 Modified 2026-04-23 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