Lm-sys vulnerabilities
We track 6 vulnerabilities in Lm-sys products across 2 products. 6 are rated high or critical, and none are known to be exploited. The most recent was published on September 4, 2026.
Latest Lm-sys vulnerabilities
- 9.4 Critical severity
FastChat: Missing Authentication for Critical Functionality
FastChat contains an authentication bypass vulnerability in the /register_worker endpoint that allows unauthenticated attackers to register arbitrary worker addresses and perform server-side request forgery. Attackers can register malicious workers under victi
- 7.5 High severity
lm-sys/fastchat: Server-Side Request Forgery
A Server-Side Request Forgery (SSRF) vulnerability was identified in the lm-sys/fastchat web server, specifically in the affected version git 2c68a13. This vulnerability allows an attacker to access internal server resources and data that are otherwise inacces
- 7.5 High severity
lm-sys/fastchat: Server-Side Request Forgery
A Server-Side Request Forgery (SSRF) vulnerability exists in lm-sys/fastchat version 0.2.36. The vulnerability is present in the `/queue/join?` endpoint, where insufficient validation of the path parameter allows an attacker to send crafted requests. This can
- 7.5 High severity
lm-sys/fastchat: Uncontrolled Resource Consumption
A Denial of Service (DoS) vulnerability exists in the file upload feature of lm-sys/fastchat version 0.2.36. The vulnerability is due to improper handling of form-data with a large filename in the file upload request. An attacker can exploit this by sending a
- 7.5 High severity
lm-sys/fastchat: Loop with Unreachable Exit Condition
In lm-sys/fastchat Release v0.2.36, the server fails to handle excessive characters appended to the end of multipart boundaries. This flaw can be exploited by sending malformed multipart requests with arbitrary characters at the end of the boundary. Each extra
- 9.3 Critical severity
lm-sys/fastchat: Server-Side Request Forgery
A Server-Side Request Forgery (SSRF) vulnerability exists in the POST /worker_generate_stream API endpoint of the Controller API Server in lm-sys/fastchat, as of commit e208d5677c6837d590b81cb03847c0b9de100765. This vulnerability allows attackers to exploit th