CVE-2019-9637

An issue was discovered in PHP before 7.1.27, 7.2.x before 7.2.16, and 7.3.x before 7.3.3. Due to the way rename() across filesystems is implemented, it is possible that file being renamed is briefly available with wrong permissions while the rename is ongoing, thus enabling unauthorized users to access the data.

Source: CVE-2019-9637