What is CVE-2025-46734?

CVE-2025-46734 is a medium-severity vulnerability in Thephpleague Commonmark, classified under Cross-site Scripting. CVSS score: 6.4/10. Published 2025-05-05.

How severe is CVE-2025-46734?

Medium severity. CVSS v3 base score is 6.4 out of 10.

XSS in Thephpleague Commonmark

CVE-2025-46734

league/commonmark is a PHP Markdown parser. A cross-site scripting (XSS) vulnerability in the Attributes extension of the league/commonmark library (versions 1.5.0 through 2.6.x) allows remote attackers to insert malicious JavaScript calls…

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.001 (15.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N.

Affected products

Thephpleague Commonmark — versions < 2.7.0

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

https://github.com/thephpleague/commonmark/security/advisories/GHSA-3527-qv2q-pfvx (x_refsource_CONFIRM)
https://github.com/thephpleague/commonmark/commit/f0d626cf05ad3e99e6db26ebcb9091b6cd1cd89b (x_refsource_MISC)

Frequently asked questions

What is CVE-2025-46734?: CVE-2025-46734 is a medium-severity vulnerability in Thephpleague Commonmark, classified under Cross-site Scripting. CVSS score: 6.4/10. Published 2025-05-05.
How severe is CVE-2025-46734?: Medium severity. CVSS v3 base score is 6.4 out of 10.