This log clearly shows an HTTP GET request attempting to exploit a web server using a directory traversal attack with Unicode encoding:

The URL contains:/msadc/..%c0%af../..%c0%af../winnt/system32/cmd.exe?/c+dir+c:

%c0%af is a known Unicode-encoded sequence used to bypass input validation filters.It translates to the forward slash character “/” when interpreted by vulnerable versions of Microsoft IIS (specifically IIS 4.0 and 5.0).

This type of attack attempts to:

Traverse out of the web root directory (via encoded ../ sequences)

Access cmd.exe in the Windows system32 directory

Execute operating system commands such as dir c: (list contents of drive C)

From CEH v13 Official Courseware:

Module 14: Hacking Web Servers

Topic: Unicode Directory Traversal Vulnerability (IIS-specific)

CEH v13 Study Guide states:

“A Unicode Directory Traversal Attack takes advantage of improper input sanitization by encoding traversal characters (../) as Unicode (e.g., %c0%af). This bypasses input filters and accesses restricted directories such as system32.”

Incorrect Options:

A. Hexcode Attack: Not a formal classification; here Unicode encoding is used.

B. Cross-Site Scripting: Involves injecting scripts into a web page, unrelated to filesystem traversal.

C. Multiple Domain Traversal: Not a valid or recognized attack type.