CVE-2024-38527
Cross-site Scripting in ZenUML
Description
### Summary Markdown-based comments in the ZenUML diagram syntax are susceptible to Cross-site Scripting (XSS). ### Details The comment feature allows the user to attach small notes for reference. This feature allows the user to enter in their comment in markdown comment, allowing them to use common markdown features, such as `**` for bolded text. However, the markdown text is currently not sanitized before rendering, allowing an attacker to enter a malicious payload for the comment which leads to XSS. https://github.com/mermaid-js/zenuml-core/blob/dcfee8cde42673c09e19401f43ad8506658c8442/src/components/DiagramFrame/SeqDiagram/MessageLayer/Block/Statement/Comment/Comment.vue#L65 ### PoC ``` // p<img onerror=alert(1) src=""/> A->B:hi ``` Above is a POC diagram payload that results in an XSS. Here is a similar POC in mermaid.live: https://mermaid.live/edit#pako:eNpNjrFuwyAQhl8F3dRK1DaQGhs1kVq1Y6duFQsylwTVgEWw1MTyuxc5S7df39399y0wRIug4IZh9qMOdU2mF-dPJAZMKaa9GTHlB_ZILmnYa9BQH3R4fTq8qbMDCh6TN86WhkUHQjTkM3rUoEq0Jv2Ui7CWPTPn-HUNA6icZqQwT9ZkfHfmlIwHdTTjpVC0Lsf0eVfazChMJoBa4BdUL6uGC8n7TrCGd5zCFRRnXbVjvBVNK3gJXbtSuMVYSlnFC-Kyf961UshWbmXf2-y_xcf29c7WP2yrVC0 ### Impact This puts existing applications that use ZenUML **unsandboxed** at risk of arbitrary JavaScript execution when rendering user-controlled diagrams.
How to fix CVE-2024-38527
To remediate CVE-2024-38527, upgrade the affected package to a fixed version below.
- —upgrade to 3.23.25 or later
Is CVE-2024-38527 being exploited?
Low — EPSS is 0.1%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0, < 3.23.25