CVE-2026-6608

Exploitation

Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.

SSVC decision

• ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
• AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.31% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 23.3% of scored records. A rank, not a probability.

NVD base score

5.5 (CVSS v4.0), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

NVD analysis status

Deferred. NVD last modified this record on 2026-06-17.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-04-20 05:15Z4 MO AGO

Last updated

2026-04-20 14:57Z4 MO AGO

Reserved

2026-04-19

Assigning CNA

VulDB

Record state

PUBLISHED

Severity

Medium (CVSS 6.9)

CNA CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P

Weaknesses

• CWE-670Always-Incorrect Control Flow ImplementationClass

Data version

5.2

Document digest

194e245eb952d9a3950c43563cea503e061fb40ba8d0b77394b85141cfce90d9

• vuldb.comVDB-358243 | lm-sys fastchat Arena Side-by-Side View add_text control flowhttps://vuldb.com/vuln/358243vdb-entrytechnical-description
• vuldb.comVDB-358243 | CTI Indicators (IOB, IOC, IOA)https://vuldb.com/vuln/358243/ctisignaturepermissions-required
• vuldb.comSubmit #792228 | LM-Sys FastChat <= 0.2.36 Content Moderation Bypass (CWE-670)https://vuldb.com/submit/792228third-party-advisory
• github.comhttps://github.com/lm-sys/FastChat/issues/3834issue-tracking
• gist.github.comhttps://gist.github.com/YLChen-007/e45039d23e698222d887ee09735d9d36exploit
• github.comhttps://github.com/lm-sys/FastChat/product