Suspicious Windows Paths in URI Query
This rule detects suspicious Windows file path strings (e.g., 'C:/Users', 'C:/Windows', 'C:/Program Files') within the URI query component of web requests. The presence of such strings in a URI could indicate an attempt to exfiltrate data from a Windows system or communicate with a webshell that is attempting to access local files or directories. The rule looks for both standard and URL-encoded variations of these paths.
Sigma

