CVE-2026-96560: LightLLM through 1.2.0 Unauthenticated Remote Code Execution via NCCL PD RPyC Control Channel
LightLLM through 1.2.0 contains a remote code execution vulnerability in the KV-transfer worker when started with --pdtransmode nccl, which exposes an unauthenticated RPyC control channel that deserializes attacker-supplied data. Attackers can send malicious pickled objects to the exposed RPyC ThreadedServer to execute arbitrary code with the privileges of the LightLLM service account.
Affected Software
Event History
Frequently Asked Questions
Which deployments are affected?
LightLLM deployments through version 1.2.0 are affected when the KV-transfer worker is started with --pd_trans_mode nccl. The vulnerable configuration exposes an RPyC ThreadedServer control channel.
What does an attacker need to exploit this issue?
An attacker needs network access to the exposed RPyC control channel. No authentication, privileges, or user interaction are required.
What is the impact of successful exploitation?
An attacker can send malicious pickled objects that are deserialized by the control channel, resulting in arbitrary code execution. Code runs with the privileges of the LightLLM service account.
How can I determine whether my deployment is exposed?
Check whether the KV-transfer worker was launched with --pd_trans_mode nccl and whether its RPyC ThreadedServer control channel is reachable by untrusted network clients. Deployments not using that mode are not identified by the provided information as affected.