XSS in Mermaid-js Mermaid

CVE-2025-54880

Mermaid is a JavaScript based diagramming and charting tool that uses Markdown-inspired text definitions and a renderer to create and modify complex diagrams. In the default configuration of mermaid 11.9.0 and earlier, user supplied input…

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.004 (28.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-54880?
CVE-2025-54880 is a medium-severity vulnerability in Mermaid-js Mermaid, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2025-08-19.
How severe is CVE-2025-54880?
Medium severity. CVSS v3 base score is 6.1 out of 10.
Is CVE-2025-54880 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.