Vulnerability · Published Sep 23, 2026 · Assigned by VulnCheck

CVE-2026-96560LightLLM through 1.2.0 Unauthenticated Remote Code Execution via NCCL PD RPyC Control Channel

Critical 9.8

In plain English

A critical-severity unsafe deserialization in LightLLM from ModelTC. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.2% (higher than 68% of all known vulnerabilities).

Severity (CVSS 3.1)9.8Critical

Exploit odds (30 days)1.2%top 31.8% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

LightLLM through 1.2.0 contains a remote code execution vulnerability in the KV-transfer worker when started with --pd_trans_mode 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 products (as reported)

Vendor	Product	Versions
ModelTC	LightLLM	0 – through 1.2.0

Weakness: CWE-502 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

GitHub Issue #1590 issue-tracking
https://github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/router/model_infer/mode_backend/pd/nccl_kv_transporter.py#L437-L461 technical-description
https://github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/router/model_infer/mode_backend/pd/nccl_kv_transporter.py#L411-L415 technical-description
https://github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/router/model_infer/mode_backend/pd/nccl_kv_transporter.py#L247-L249 technical-description
https://github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/router/model_infer/mode_backend/pd/kv_transporter.py#L20-L36 technical-description
https://github.com/ModelTC/lightllm product
VulnCheck Advisory: LightLLM through 1.2.0 Unauthenticated Remote Code Execution via NCCL PD RPyC Control Channel third-party-advisory