Vulnerability · Published Sep 29, 2026 · Assigned by VulnCheck

CVE-2026-103042LightLLM through 1.2.0 Unauthenticated Memory Exhaustion via NCCL Control Channel set_value

High 7.5

In plain English

A high-severity resource allocation without limits in LightLLM from ModelTC. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 51% of all known vulnerabilities).

Severity (CVSS 3.1)7.5High

Exploit odds (30 days)0.6%top 48.9% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

LightLLM through 1.2.0 contains a memory exhaustion vulnerability in the NCCL control channel when started with --pd_trans_mode nccl, allowing unauthenticated attackers to exhaust KV-transfer worker memory. Attackers can call the exposed_set_value method to store unbounded key-value pairs without size limits, causing the worker process to crash and triggering node failure.

Affected products (as reported)

Vendor	Product	Versions
ModelTC	LightLLM	0 – through 1.2.0

Weakness: CWE-770 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

GitHub Issue #1595 issue-tracking
https://github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/router/model_infer/mode_backend/pd/nccl_kv_transporter.py#L416-L420 technical-description
https://github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/router/model_infer/mode_backend/pd/nccl_kv_transporter.py#L474-L485 technical-description
https://github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/router/model_infer/mode_backend/pd/base_kv_move_manager.py#L121-L122 technical-description
https://github.com/ModelTC/LightLLM product
VulnCheck Advisory: LightLLM through 1.2.0 Unauthenticated Memory Exhaustion via NCCL Control Channel set_value third-party-advisory