The string you provided, callback-url-file-3A-2F-2F-2Fhome-2F-2A-2F.aws-2Fcredentials , appears to be a URL-encoded path designed to target sensitive local files, specifically the located at file:///home/*/.aws/credentials .
The keyword refers to a high-risk security payload used by ethical hackers and cybercriminals to test for Server-Side Request Forgery (SSRF) and Local File Inclusion (LFI) vulnerabilities. This specific string is an encoded attempt to force a web application to read a sensitive AWS credential file from its own internal filesystem. Deciphering the Payload callback-url-file-3A-2F-2F-2Fhome-2F-2A-2F.aws-2Fcredentials
: Unlike temporary instance metadata credentials, these local credentials often do not expire until manually rotated. Rhino Security Labs Remediation & Best Practices Deciphering the Payload : Unlike temporary instance metadata
~/.aws/credentials (AWS Access Key ID and Secret Access Key). It indicates an attempt to bridge the gap
The keyword callback-url-file-3A-2F-2F-2Fhome-2F-2A-2F.aws-2Fcredentials is a red flag for any system administrator. It indicates an attempt to bridge the gap between a web vulnerability and a full cloud account breach. By moving toward and away from static credential files , organizations can render these types of attacks useless.