---
id: "CVE-2026-119979"
kind: "vulnerability"
aliases: ["CVE-2026-119979"]
title: "LM Studio: crafted model download writes files and runs attacker Python on launch"
severity: "high"
cvss: 8.8
epss: null
exploited: false
status: "open"
category: "ai-tooling"
products: []
ecosystems: []
tags: ["ai-tooling", "developer-desktop", "lm-studio", "local-llm"]
not_affected_if: ["trusted-model-sources-only", "version-0.4.22+1-or-later"]
published_at: "2026-10-30T18:17:27+00:00"
first_seen_at: "2026-10-30T18:55:30+00:00"
updated_at: "2026-10-30T18:56:30+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-119979", "first_seen_at": "2026-10-30T18:55:30+00:00"}]
---

# LM Studio: crafted model download writes files and runs attacker Python on launch

LM Studio before 0.4.22+1 fails to block backslash-separated path traversal in its model downloader, so a crafted model repository can write files outside the models directory. The planted plugin and MCP bridge config files cause an attacker-supplied Python payload to run every time LM Studio launches.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed LM Studio version in the app's About screen or package metadata; versions below `0.4.22+1` are in scope.
- Look for unexpected `manifest.json`, `install-state.json` or `mcp-bridge-config.json` files in LM Studio's plugin directories and outside the models directory.

## Fix

- LM Studio: move to `0.4.22+1` or later.

## Timeline

- 2026-10-30T18:55:30+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-119979

## From the sources

LM Studio before 0.4.22+1 contains a path traversal vulnerability in the model downloader's resolveDownloadRequest that allows attackers to write files outside the models directory using backslash-separated traversal filenames. Attackers can trick users into downloading a crafted model repository that plants a plugin manifest.json, install-state.json and mcp-bridge-config.json, running an attacker-supplied Python payload on every launch.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_