XSS in Creativemindssolutions Cm E-Mail Blacklist – Simple Email Filtering For Safer Registration

CVE-2026-0691

The CM E-Mail Blacklist – Simple email filtering for safer registration plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'black_email' parameter in all versions up to, and including, 1.6.2. This is due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with administrator-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This only affects multi-site installations and installations where unfiltered_html has been disabled.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.003 (17.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.4 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-0691?
CVE-2026-0691 is a medium-severity vulnerability in Creativemindssolutions Cm E-Mail Blacklist – Simple Email Filtering For Safer Registration, classified under Cross-site Scripting. CVSS score: 4.4/10. Published 2026-01-17.
How severe is CVE-2026-0691?
Medium severity. CVSS v3 base score is 4.4 out of 10.