This indicates an attack attempt to exploit a Directory Traversal Vulnerability in Responsive File Manager.
A remote, unauthenticated attacker could exploit this vulnerability by sending a crafted HTTP request to a vulnerable server. Successful exploitation could allow an attacker to read files from arbitrary locations on the server.
Responsive File Manager 9.13.4
Information Disclosure: Remote attackers can gain sensitive information from vulnerable systems.
Apply the most recent upgrade or patch from the vendor: