CVE-2020-13664: Drupal

High severity, CVSS 8.8. EPSS: 3% chance of exploitation in the next 30 days.

Arbitrary PHP code execution vulnerability in Drupal Core under certain circumstances. An attacker could trick an administrator into visiting a malicious site that could result in creating a carefully named directory on the file system. With this directory in place, an attacker could attempt to brute force a remote code execution vulnerability. Windows servers are most likely to be affected. This issue affects: Drupal Drupal Core 8.8.x versions prior to 8.8.8; 8.9.x versions prior to 8.9.1; 9.0.1 versions prior to 9.0.1.

Affected products

• Drupal Drupal: from 8.8.0, before 8.8.8 (fixed in 8.8.8); from 8.9.0, before 8.9.1 (fixed in 8.9.1); from 9.0.0, before 9.0.1 (fixed in 9.0.1)

Published 2021-05-05. Last modified 2026-06-17.