What is CVE-2025-9540?

CVE-2025-9540 is a medium-severity vulnerability in Markup Markdown, classified under CWE-79 CROSS-SITE SCRIPTING (XSS). CVSS score: 4.7/10. Published 2025-09-22.

How severe is CVE-2025-9540?

Medium severity. CVSS v3 base score is 4.7 out of 10.

Is CVE-2025-9540 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Vulnerability in Markup Markdown

CVE-2025-9540

The Markup Markdown WordPress plugin before 3.20.10 allows links to contain JavaScript which could allow users with the contributor role and above to perform Stored Cross-Site Scripting attacks.

EPSS: 0.002 (12.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.7 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L.

Affected products

Unknown Markup Markdown — versions 0

Public proof-of-concept exploits

fkie-cad/nvd-json-data-feeds

References

contact@wpscan.com (technical-description, exploit, vdb-entry)

Frequently asked questions

What is CVE-2025-9540?: CVE-2025-9540 is a medium-severity vulnerability in Markup Markdown, classified under CWE-79 CROSS-SITE SCRIPTING (XSS). CVSS score: 4.7/10. Published 2025-09-22.
How severe is CVE-2025-9540?: Medium severity. CVSS v3 base score is 4.7 out of 10.
Is CVE-2025-9540 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.