This indicates an attack attempt to exploit a Directory Traversal vulnerability in WordPress.
The vulnerability is due to insufficient sanitizing of user supplied inputs in the application. Successful attacks may allow a remote attackers to use a specially crafted request with directory-traversal sequences to retrieve sensitive information.
WordPress 5.0.3 and prior versions.
Information Disclosure: Remote attackers can gain sensitive information from vulnerable systems.
Apply patch if available from the vendor's website.