CVE-2025-67744
📋 TL;DR
DeepChat versions before 0.5.3 contain a critical vulnerability where unsafe Mermaid diagram rendering allows arbitrary JavaScript execution. This XSS flaw escalates to full remote code execution due to exposed Electron IPC interfaces, enabling attackers to execute system commands. All users running vulnerable DeepChat instances are affected.
💻 Affected Systems
- DeepChat
📦 What is this software?
Deepchat by Thinkinai
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise allowing attacker to execute arbitrary commands, steal data, install malware, or pivot to other systems.
Likely Case
Attacker gains remote code execution on the DeepChat server, potentially accessing sensitive AI models, user data, and system resources.
If Mitigated
If proper network segmentation and least privilege are implemented, impact may be limited to the DeepChat application and its data.
🎯 Exploit Status
Exploitation requires crafting malicious Mermaid diagrams but does not require authentication.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 0.5.3
Vendor Advisory: https://github.com/ThinkInAIXYZ/deepchat/security/advisories/GHSA-w8w8-82pv-5rg9
Restart Required: Yes
Instructions:
1. Stop DeepChat service. 2. Update to version 0.5.3 using package manager or manual installation. 3. Restart DeepChat service.
🔧 Temporary Workarounds
Disable Mermaid rendering
allTemporarily disable Mermaid diagram rendering functionality
Modify DeepChat configuration to disable Mermaid diagram support
Network isolation
allRestrict network access to DeepChat instances
Configure firewall rules to limit access to trusted IPs only
🧯 If You Can't Patch
- Isolate DeepChat instances on separate network segments with strict firewall rules
- Implement web application firewall (WAF) rules to block suspicious Mermaid content
🔍 How to Verify
Check if Vulnerable:
Check DeepChat version - if version is below 0.5.3, system is vulnerableCheck Version:
Check DeepChat configuration file or run: deepchat --versionVerify Fix Applied:
Verify DeepChat version is 0.5.3 or higher after update📡 Detection & Monitoring
Log Indicators:
- Unusual Mermaid diagram rendering requests
- Suspicious JavaScript execution in logs
- Unexpected system command execution
Network Indicators:
- Unusual outbound connections from DeepChat server
- Traffic patterns suggesting command and control
SIEM Query:
source="deepchat" AND (mermaid OR diagram) AND (javascript OR eval OR exec)