CVE-2021-39320: Underconstruction Project Underconstruction

Medium severity, CVSS 6.1. EPSS: 2.3% chance of exploitation in the next 30 days.

The underConstruction plugin <= 1.18 for WordPress echoes out the raw value of `$GLOBALS['PHP_SELF']` in the ucOptions.php file. On certain configurations including Apache+modPHP, this makes it possible to use it to perform a reflected Cross-Site Scripting attack by injecting malicious code in the request path.

Affected products

• Underconstruction Project Underconstruction: before 1.19 (fixed in 1.19)

Published 2021-09-01. Last modified 2026-06-17.