CVE-2026-93839
CriticalCVSS 9.8Summary
LightLLM through version 1.2.0 contains an authentication bypass vulnerability in the /pd_register WebSocket endpoint that allows unauthenticated attackers to register arbitrary nodes by supplying crafted JSON without peer address validation. Attackers can disclose full user prompts routed to their socket, trigger denial of service by replacing legitimate nodes, or make the PD Master issue requests to internal network addresses.
Risk Assessment
An attacker can intercept sensitive user prompts, disrupt operations via DoS, and use the PD Master to scan or attack the internal network. This may lead to data leakage and compromise of environment integrity.
Recommendation
Update LightLLM to a version later than 1.2.0 if a fix is available, or restrict access to the /pd_register endpoint to trusted networks. Implement authentication and peer address validation for WebSocket connections.
Other vulnerabilities in LightLLM
See all- CVE-2026-90919Critical
LightLLM through 1.2.0 contains a remote code execution vulnerability in the Config Server's unauthenticated /visual_register WebSocket endpoint, which passes the first client frame directly to pickle.loads(). Attackers can reach the Config Server port and send a malicious serialized payload with a __reduce__ method to execute arbitrary code with Config Server process privileges.
- CVE-2026-26220Critical
LightLLM version 1.1.0 and prior contain an unauthenticated remote code execution vulnerability in PD (prefill-decode) disaggregation mode. The PD master node exposes WebSocket endpoints that receive binary frames and pass the data directly to pickle.loads() without authentication or validation. A remote attacker who can reach the PD master can send a crafted payload to achieve arbitrary code execution.
Original NVD description (English source)
LightLLM through 1.2.0 contains an authentication bypass vulnerability in the /pd_register WebSocket endpoint that allows unauthenticated attackers to register arbitrary nodes by supplying crafted JSON without peer address validation. Attackers can disclose full user prompts routed to their socket, trigger denial of service by replacing legitimate nodes, or make the PD Master issue requests to internal network addresses.