https://cve.radiocsirt.org/rss/recent/all/10 Most recent entries from all 2026-10-06T08:45:02.657860+00:00 Vulnerability-Lookup csirt@opendfir.org python-feedgen Contains only the most 10 recent entries. https://cve.radiocsirt.org/vuln/euvd-2026-6043 EUVD-2026-6043 2026-10-06T08:45:02.661319+00:00 EUVD-2026-6043 https://cve.radiocsirt.org/vuln/fkie_cve-2024-38527 fkie_cve-2024-38527 2026-10-06T08:45:02.661355+00:00

ZenUML is JavaScript-based diagramming tool that requires no server, using Markdown-inspired text definitions and a renderer to create and modify sequence diagrams. Markdown-based comments in the ZenUML diagram syntax are susceptible to Cross-site Scripting (XSS). 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. This puts existing applications that use ZenUML unsandboxed at risk of arbitrary JavaScript execution when rendering user-controlled diagrams. This vulnerability was patched in version 3.23.25,

 https://cve.radiocsirt.org/vuln/ghsa-q6xv-jm4v-349h GHSA-q6xv-jm4v-349h — Cross-site Scripting in ZenUML 2026-10-06T08:45:02.661434+00:00

Affected: npm: @zenuml/core

### 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.