CVE-2026-71437
Mermaid Architecture diagrams are vulnerable to prototype pollution
CVSS Score
0.0
EPSS Score
0.0%
EPSS Percentile
0th
Mermaid is a JavaScript tool that uses Markdown-inspired text to create and modify diagrams and charts. From version 11.5.0 until 11.16.1, Mermaid Architecture Diagrams are vulnerable to prototype pollution when a diagram defines a group with an id of __proto__. Because the group id is used directly as an object property key without validation, an attacker who can supply diagram text can pollute Object.prototype, potentially affecting the behavior of the embedding application. This issue is fixed in version 11.16.1.
| CWE | CWE-1321 |
| Vendor | mermaid-js |
| Product | mermaid |
| Published | Aug 6, 2026 |
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Affected Versions
mermaid-js / mermaid
>= 11.5.0, < 11.16.1
References
github.com: https://github.com/mermaid-js/mermaid/security/advisories/GHSA-3rrr-jr9j-h3q3 github.com: https://github.com/mermaid-js/mermaid/pull/8022 github.com: https://github.com/mermaid-js/mermaid/commit/99af3fc35ef0a9a9c8c6314521344d67523ddccf github.com: https://github.com/mermaid-js/mermaid/releases/tag/[email protected]