CVE-2024-38527: XSS (CVSS 5.4)

Description

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,

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CVSS v3.1 Score

5.4

MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

References

Other References

https://github.com/mermaid-js/zenuml-core/commit/ad7545b33f5f27466cbf357beb65969ca1953e3c https://github.com/mermaid-js/zenuml-core/security/advisories/GHSA-q6xv-jm4v-349h https://github.com/mermaid-js/zenuml-core/commit/ad7545b33f5f27466cbf357beb65969ca1953e3c https://github.com/mermaid-js/zenuml-core/security/advisories/GHSA-q6xv-jm4v-349h

Frequently Asked Questions

What is 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, It has a CVSS v3.1 base score of 5.4 (MEDIUM).

How severe is CVE-2024-38527? +

CVE-2024-38527 has a CVSS v3.1 score of 5.4 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

How do I check if I'm vulnerable to CVE-2024-38527? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2024-38527