This indicates an attack attempt to exploit a Directory Traversal Vulnerability in Responsive File Manager.
The vulnerability is due to an error in the vulnerable application when handling a maliciously crafted request. An attacker can exploit this to read arbitrary files on the affected machine via a crafted request.
Responsive File Manager Prior to 9.13.4
Information Disclosure: Remote attackers can gain sensitive information from vulnerable systems.
Apply the most recent upgrade or patch from the vendor: