Critical severity · published Dec 3, 2025
CVE-2025-66222
DeepChat Cross-Site Scripting(XSS) escalate to Remote Code Execution(RCE)
9.6
CVSS
0.6%
EPSS
No
On KEV
Description
DeepChat is a smart assistant uses artificial intelligence. In 0.5.0 and earlier, there is a Stored Cross-Site Scripting (XSS) vulnerability in the Mermaid diagram renderer allows an attacker to execute arbitrary JavaScript within the application context. By leveraging the exposed Electron IPC bridge, this XSS can be escalated to Remote Code Execution (RCE) by registering and starting a malicious MCP (Model Context Protocol) server.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 49% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DE
deepchat · ThinkInAIXYZ
< 0.5.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-66222
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-66222
Patch
https://github.com/ThinkInAIXYZ/deepchat/commit/371ca7b42e3685aee6e3f0c61e85277ed1ff4db7
Exploit
https://github.com/ThinkInAIXYZ/deepchat/security/advisories/GHSA-v8v5-c872-mf8r
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