Description
DeepChat is an open-source AI chat platform that supports cloud models and LLMs. Versions 0.5.1 and below are vulnerable to XSS attacks through improperly sanitized Mermaid content. The recent security patch for MermaidArtifact.vue is insufficient and can be bypassed using unquoted HTML attributes combined with HTML entity encoding. Remote Code Execution is possible on the victim's machine via the electron.ipcRenderer interface, bypassing the regex filter intended to strip dangerous attributes. There is no fix at time of publication.
Affected products
thinkinai: deepchat
References2
- github.com/ThinkInAIXYZ/deepchat/security/advisories/GHSA-h9f5-… ExploitVendor Advisory
- github.com/ThinkInAIXYZ/deepchat/security/advisories/GHSA-h9f5-… ExploitVendor Advisory
Metrics
- CVSS 3.1
-
9.6
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 50 · as of 11 November 2026
- CWE
- CWE-79CWE-80CWE-94
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.