CVE-2024-7983
📋 TL;DR
This vulnerability in open-webui version 0.3.8 exposes an unauthenticated markdown-to-HTML conversion endpoint. Attackers can send specially crafted markdown payloads that cause excessive server processing time, leading to denial of service where the server becomes unresponsive to legitimate requests. Anyone running open-webui 0.3.8 with default configuration is affected.
💻 Affected Systems
- open-webui
📦 What is this software?
Open Webui by Openwebui
⚠️ Risk & Real-World Impact
Worst Case
Complete service unavailability for all users until the malicious conversion completes or the server is restarted, potentially causing extended downtime.
Likely Case
Temporary service degradation or intermittent unresponsiveness affecting user experience and system reliability.
If Mitigated
Minimal impact with proper rate limiting, authentication, or input validation in place.
🎯 Exploit Status
Exploitation requires sending a malicious markdown payload to the vulnerable endpoint without authentication.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 0.3.9 or later
Vendor Advisory: https://huntr.com/bounties/f8156ca5-1328-480f-a72b-8d3dfdad87dc
Restart Required: No
Instructions:
1. Update open-webui to version 0.3.9 or later using your package manager or installation method. 2. Verify the update completed successfully. 3. No restart required as this is a web application.
🔧 Temporary Workarounds
Implement authentication
allAdd authentication requirements to the markdown conversion endpoint
Rate limiting
allImplement rate limiting on the vulnerable endpoint to prevent abuse
🧯 If You Can't Patch
- Implement network-level access controls to restrict access to the vulnerable endpoint
- Deploy a web application firewall with DoS protection rules
🔍 How to Verify
Check if Vulnerable:
Check if running open-webui version 0.3.8 and if the markdown conversion endpoint is accessible without authenticationCheck Version:
Check package.json or installation documentation for version informationVerify Fix Applied:
Verify open-webui version is 0.3.9 or later and test that the markdown endpoint now requires authentication or has proper input validation📡 Detection & Monitoring
Log Indicators:
- Unusually long processing times for markdown conversion requests
- Multiple rapid requests to the markdown endpoint
- Server error logs indicating timeout or resource exhaustion
Network Indicators:
- High volume of requests to /api/markdown or similar endpoints
- Unusually large payloads sent to conversion endpoints
SIEM Query:
source="webui" AND (uri="/api/markdown" OR uri="/convert") AND response_time>5000