GitHub Advisoryadvisory · npm
GHSA-2v8p-3f2j-5mp7 Mermaid XY Charts are vulnerable to an infinite loop DoS
MEDIUM
Official page ↗
- Aliases
- CVE-2026-71436
- Ecosystem
- npm
- Packages
- mermaid
- Severity
- Moderate
- CVSS vector
- CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:L
- Weaknesses
- CWE-1325, CWE-835
- Reviewed
- 2026-08-06
Affected packages
• npm mermaid: >= 10.6.0, < 10.9.8 → fixed in 10.9.8
• npm mermaid: >= 11.0.0-alpha.1, < 11.16.1 → fixed in 11.16.1
Description
Impact
Mermaid XY Charts are vulnerable to an infinite loop DoS attack in the `setXAxisRangeData()`, when configuring an X-Axis with invalid parameters.
As each loop appends an element to an array, this would generally only cause an `RangeError: Invalid array length` to appear after a few seconds, but may cause the page/JavaScript process to crash due to memory exhaustion, depending on the environment.
Proof-of-concept
```txt
xychart
x-axis 1 --> 1
line [1, 2]
```
Patches
This has been patched in https://github.com/mermaid-js/mermaid/commit/630aa7e5dd417e1f56bff2a1ce8df2c5ad08d289 and released in Mermaid v11.16.1.
A backport has been made for the v10 branch in ef60adc837d9d5107af21285f01e83dea309bd0a and was released in Mermaid v10.9.8
Workarounds
There are no known workarounds. Please update to the latest version or apply the patch.
References
• https://github.com/mermaid-js/mermaid/commit/630aa7e5dd417e1f56bff2a1ce8df2c5ad08d289
• https://github.com/mermaid-js/mermaid/releases/tag/mermaid%4011.16.1
• https://github.com/mermaid-js/mermaid/commit/ef60adc837d9d5107af21285f01e83dea309bd0a
• https://github.com/mermaid-js/mermaid/releases/tag/v10.9.8
Related
Alias · CVE (1)
- CVE-2026-71436 Mermaid is a JavaScript tool that uses Markdown-inspired text to create and modify diagrams and charts. vulnerability
References
- https://github.com/mermaid-js/mermaid/security/advisories/GHSA-2v8p-3f2j-5mp7 web
- https://github.com/mermaid-js/mermaid/pull/8022 web
- https://github.com/mermaid-js/mermaid/commit/630aa7e5dd417e1f56bff2a1ce8df2c5ad08d289 web
- https://github.com/mermaid-js/mermaid/commit/ef60adc837d9d5107af21285f01e83dea309bd0a web
- https://github.com/mermaid-js/mermaid package
- https://github.com/mermaid-js/mermaid/releases/tag/[email protected] web
- https://github.com/mermaid-js/mermaid/releases/tag/v10.9.8 web