CVE-2026-6608

lm-sys fastchat Arena Side-by-Side View add_text control flow

MEDIUM
5.3
CVSS Score
Published: April 20, 2026 at 05:15 AM UTC
Updated: June 17, 2026 at 11:01 AM UTC
1 product affected across 1 vendorFastChat

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Severity
MEDIUM5.3
Exploit prediction
EPSS 0.3%
SSVC
PoC

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.

Affected

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

References (6)

VDB EntryTechnical Description
Source: cverecord
https://vuldb.com/vuln/358243
SignaturePermissions Required
Source: cverecord
https://vuldb.com/vuln/358243/cti
Third Party Advisory
Source: cverecord
https://vuldb.com/submit/792228
Issue Tracking
Source: cverecord
https://github.com/lm-sys/FastChat/issues/3834
Product
Source: cverecord
https://github.com/lm-sys/FastChat/

SSVC — Action Prioritization

SSVCPoCAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.3MEDIUMVulDB
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-670

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