# CVE-2026-103042 — ModelTC LightLLM

> As of 2026-09-29, CVE-2026-103042 is a HIGH-severity vulnerability in ModelTC LightLLM, CVSS v3.1 7.5. No Threadlinqs-tracked threat campaign has been attributed to CVE-2026-103042 as of 2026-09-29; the identifier is re-checked against the Threadlinqs threat corpus on every daily ingest.

**Last updated:** 2026-09-29

## What is CVE-2026-103042?

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.

The record classifies CVE-2026-103042 under weakness class [CWE-770](https://intel.threadlinqs.com/cwe/CWE-770). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction, and has high impact on availability. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 6 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 7.5 — HIGH (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **CVSS v4.0 base score:** 8.7 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 3.8/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-09-29

## Is CVE-2026-103042 being exploited?

It currently carries a trending score of 30 in the Threadlinqs vulnerability feed.

## Affected products and versions

- **ModelTC**: LightLLM

## How to fix CVE-2026-103042

No vendor patch reference has been recorded for CVE-2026-103042 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2026-103042

No threat campaign in the Threadlinqs corpus currently references CVE-2026-103042, in its CVE list or as an indicator. The linkage is recomputed from the live corpus on every daily ingest, so this section fills in as soon as a tracked campaign cites the identifier.

## Sources

Enriched from CVE.org. Last verified by Threadlinqs on 2026-09-30.

**Technical analysis**

- [github.com — technical description](https://github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/router/model_infer/mode_backend/pd/nccl_kv_transporter.py#L416-L420)
- [github.com — technical description (nccl kv transporter)](https://github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/router/model_infer/mode_backend/pd/nccl_kv_transporter.py#L474-L485)
- [github.com — technical description (base kv move manager)](https://github.com/ModelTC/lightllm/blob/v1.2.0/lightllm/server/router/model_infer/mode_backend/pd/base_kv_move_manager.py#L121-L122)

**Third-party advisory**

- [vulncheck.com — third party advisory](https://www.vulncheck.com/advisories/lightllm-through-1.2.0-unauthenticated-memory-exhaustion-via-nccl-control-channel-set-value)

**Issue tracking and product pages**

- [github.com — issue tracking](https://github.com/ModelTC/LightLLM/issues/1595)
- [github.com — product](https://github.com/ModelTC/LightLLM)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-103042
Full detection coverage and IOCs for threats exploiting CVE-2026-103042 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp