XSS in Mermaid-Js Zenuml-Core

CVE-2024-38527

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,

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.004 (29.5th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 30th percentile — 29.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2024-38527: held from 0.004 to 0.004.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2024-38527?
CVE-2024-38527 is a medium-severity vulnerability in Mermaid-Js Zenuml-Core, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2024-06-26.
How severe is CVE-2024-38527?
Medium severity. CVSS v3 base score is 5.4 out of 10.