Tools: CVE-2026-23733: Mermaid's Song: From Flowchart to Remote Code Execution in LobeChat

Mermaid's Song: From Flowchart to Remote Code Execution in LobeChat ## ⚠️ Exploit Status: POC ## Technical Details ## Affected Systems ## Exploit Details ## Mitigation Strategies ## References Vulnerability ID: CVE-2026-23733 CVSS Score: 6.4 Published: 2026-01-20 A stored Cross-Site Scripting (XSS) vulnerability in LobeChat's Mermaid diagram renderer allows attackers to execute arbitrary JavaScript. In the desktop Electron version, this escalates via an exposed IPC bridge to full Remote Code Execution (RCE). LobeChat trusted user-supplied text when generating Mermaid diagrams. By injecting malicious HTML into a diagram node label, an attacker can trigger XSS. In the Electron app, this XSS exploits a privileged 'runCommand' API to execute system binaries like calc.exe (or worse) on the victim's machine. Read the full report for CVE-2026-23733 on our website for more details including interactive diagrams and full exploit analysis. Templates let you quickly answer FAQs or store snippets for re-use. Are you sure you want to hide this comment? It will become hidden in your post, but will still be visible via the comment's permalink. Hide child comments as well For further actions, you may consider blocking this person and/or reporting abuse - CWE ID: CWE-94 - Attack Vector: Local (via Chat Content) - CVSS Score: 6.4 (Medium) - EPSS Score: 0.00078 - Impact: Remote Code Execution (RCE) - Exploit Status: PoC Available - Platform: Electron / Node.js - LobeChat Desktop (Windows) - LobeChat Desktop (macOS) - LobeChat Desktop (Linux) - LobeChat Web (XSS only) - LobeChat: < 2.0.0-next.180 (Fixed in: 2.0.0-next.180) - GitHub Security Advisory: Official advisory containing the PoC payload. - Input Sanitization: Strip HTML from Mermaid definitions. - Library Configuration: Set Mermaid securityLevel to 'strict'. - IPC Hardening: Remove generic 'runCommand' endpoints; define specific, parameterized allowed actions only. - Upgrade LobeChat to version 2.0.0-next.180 or later immediately. - If you cannot upgrade, disable the Mermaid artifact plugin if possible. - For developers: Review contextBridge exposure and remove any generic command execution bridges. - GitHub Advisory Database - NIST NVD Entry