CSRF in Frankkoenen Plugin Name: Login Register

CVE-2026-1503

The login_register plugin for WordPress is vulnerable to Cross-Site Request Forgery to Stored Cross-Site Scripting in all versions up to, and including, 1.2.0. This is due to missing nonce validation on the settings page and insufficient input sanitization and output escaping on the 'login_register_login_post' parameter. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page via a forged request granted they can trick an administrator into performing an action such as clicking on a link.

Vulnerability class: CSRF (Cross-Site Request Forgery)

EPSS: 0.001 (4.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-1503?
CVE-2026-1503 is a medium-severity vulnerability in Frankkoenen Plugin Name: Login Register, classified under Cross-Site Request Forgery (CSRF). CVSS score: 4.3/10. Published 2026-03-21.
How severe is CVE-2026-1503?
Medium severity. CVSS v3 base score is 4.3 out of 10.