CVE-2025-66481
BaseFortify
Publication date: 2025-12-09
Last updated on: 2025-12-11
Assigner: GitHub, Inc.
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| thinkinaixyz | deepchat | 0.5.1 |
| thinkinai | deepchat | to 0.5.1 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-79 | The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. |
| CWE-80 | The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special characters such as "<", ">", and "&" that could be interpreted as web-scripting elements when they are sent to a downstream component that processes web pages. |
| CWE-94 | The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment. |
Attack-Flow Graph
AI Powered Q&A
How can this vulnerability be detected on my network or system? Can you suggest some commands?
This vulnerability can be detected by scanning for Mermaid content in DeepChat versions 0.5.1 and below that contain unquoted HTML attributes with event handlers such as 'onerror' combined with HTML entity encoding. Since the sanitization regex only detects quoted attributes, look for patterns like onerror=alert(1) or similar unquoted event handlers in Mermaid content. You can search for suspicious Mermaid content or payloads in logs or stored data. For example, using grep or similar tools to find unquoted event handlers in Mermaid files or data: grep -P 'on\w+\s*=\s*[^"\'\s]+' *.md or *.vue files. Additionally, monitor for Electron ipcRenderer calls triggered by such payloads. Since there is no fix yet, detection relies on identifying these malicious patterns in input or stored Mermaid content. [1]
Can you explain this vulnerability to me?
This vulnerability affects DeepChat versions 0.5.1 and below, where improperly sanitized Mermaid content allows Cross-Site Scripting (XSS) attacks. The recent patch for MermaidArtifact.vue is insufficient and can be bypassed using unquoted HTML attributes combined with HTML entity encoding. This enables Remote Code Execution on the victim's machine via the electron.ipcRenderer interface by bypassing the regex filter meant to block dangerous attributes. There is currently no fix available.
How can this vulnerability impact me? :
The vulnerability can lead to Remote Code Execution on the victim's machine, allowing attackers to execute arbitrary code remotely. This can result in full compromise of the affected system, including data theft, system manipulation, or further attacks within the network.
What immediate steps should I take to mitigate this vulnerability?
Since there is no fix available at the time of publication, immediate steps include avoiding use of DeepChat versions 0.5.1 and below, especially in environments where untrusted Mermaid content is processed. Additionally, restrict or monitor usage of the electron.ipcRenderer interface to limit potential remote code execution. Applying strict input validation and sanitization on Mermaid content before rendering may help mitigate risk until an official patch is released.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
The provided resources do not contain information regarding the impact of this vulnerability on compliance with common standards and regulations such as GDPR or HIPAA.