Description
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.
References8
- github.com/ModelTC/LightLLM
- github.com/ModelTC/LightLLM/issues/1576
- github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/api_htt…
- github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/api_htt…
- github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/httpser…
- github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/httpser…
- www.vulncheck.com/advisories/lightllm-through-1.2.0-missing-aut…
- github.com/ModelTC/LightLLM/issues/1576
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 4.0
-
9.3
CRITICAL
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/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 - EPSS — exploit probability
- 1% percentile: 56 · as of 8 November 2026
- CWE
- CWE-306
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.