Drupal core - Critical - Arbitrary PHP code execution - SA-CORE-2020-005

Drupal 8 and 9 have a remote code execution vulnerability 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.