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CriticalVulnerabilityCVE-2026-75128updated 25 Oct 2026, 15:20 UTC

Langchain-Chatchat lets anyone without login run commands on the server

Anyone who can reach the server over the network can send one request and make it run system commands. In the default Docker setup those commands run as root, which means full control of the machine.

Official, 2 sources
SeverityCriticalCVSS 9.3 of 10
Being exploited?UnclearNo reports either way yet
Fix available?UnclearNo fixed version published in the sources yet
How sure is this?Official, 2 sourcesBacked by an official source

How the attack works simplified

  1. 1Remote attackerSends one HTTP request from anywhere
  2. 2POST /tools/callEndpoint accepts requests with no login
  3. 3Shell tool invokedTool is always registered and callable by name
  4. 4OS commands runExecuted as server user, root in Docker
  5. ResultAttacker controls the server

What happened

The POST /tools/call endpoint in Langchain-Chatchat invokes any registered tool by name with no authentication, and the always-registered shell tool can be called to execute arbitrary OS commands as the server user.

Why it is dangerous: A single unauthenticated request gives remote attackers arbitrary command execution, potentially as root in the shipped Docker image, allowing data theft, malware installation, or takeover of the host and connected systems.

Are you affected?

You are affected if you run Langchain-Chatchat version 0.3.1.3 or earlier with its API reachable from a network you do not fully control.

Langchain-Chatchat through 0.3.1.3

What to do

  1. Block external access to the Langchain-Chatchat API port or place it behind authentication now
  2. Check whether the service is reachable from the internet and restrict it to trusted networks
  3. Update Langchain-Chatchat to a version newer than 0.3.1.3 once a fixed release is confirmed
  4. Review server logs for requests to /tools/call and investigate any unexpected shell activity

Timeline

  1. 20 Oct 2026, 01:17 UTC
    Publicly disclosed
  2. 20 Oct 2026, 01:17 UTC
    Reported by NVD · NVD
  3. 25 Oct 2026, 15:20 UTC
    GitHub Advisory reported on it · GitHub Advisory

Sources 2 reports, oldest first

Official vendor, government CERT or advisory database

Technical details

ID
CVE-2026-75128 · GHSA-5rx2-xp53-9x5r
CVSS
9.3 / 10
EPSS
0.6% chance of exploitation within 30 days
Disclosed
20 Oct 2026, 01:17 UTC
On Zero Radar
before the radar started
Last change
25 Oct 2026, 15:20 UTC

The plain-language parts and the attack diagram were written by an AI model (anthropic/claude-haiku-5.5) from the sources above. Facts like versions, exploitation and dates come from the sources themselves. How Zero Radar works

Langchain-Chatchat lets anyone without login run commands on the server · Zero Radar