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Traffic Analysis Exercise 2025-01-22: Download From Fake Software Site

In this blog post, I show my solution to the Traffic Analysis Exercise 2025-01-22: Download From Fake Software Site by malware-traffic-analysis.net.

The questions

  • What is the IP address of the infected Windows client?
  • What is the mac address of the infected Windows client?
  • What is the host name of the infected Windows client?
  • What is the user account name from the infected Windows client?
  • What is the likely domain name for the fake Google Authenticator page?
  • What are the IP addresses used for C2 servers for this infection?

My solution

Because the background says the client has downloaded a file while searching for Google Authenticator, we first look at HTTP traffic.

Traffic Analysis

At 2025-01-22 21:45:34 the user DESKTOP-L8C5GSJ.bluemoontuesday.com (10.1.17.215) sends a DNS request for the domain: “google-authenticator.burleson-appliance.net”:

Traffic Analysis

The response is multiple IPv4 and IPv6 addresses for this domain:

Traffic Analysis

At 2025-01-22 21:45:34 the victim starts TCP/TLS session with “google-authenticator.burleson-appliance.net (104.21.64.1)”:

Traffic Analysis

The data is encrypted. No further communications from victim to 104.21.64.1.

The victim then downloads a .crx chrome extension file (starts with Cr24) from bg.microsoft.map.fastly.net (199.232.214.172):

Traffic Analysis

The victim also downloaded a Microsoft Cabinet file (.CAB) from a767.dspw65.akamai.net (23.53.127.170):

Traffic Analysis

By looking at DHCP protocol we can find the victim’s host name:

Traffic Analysis

The hostname of victim is DESKTOP-L8C5GSJ

By looking at Kerberos protocol we can figure out the Windows user name:

Traffic Analysis

The victim’s Windows user name is “shutchenson”.

We can see the victim also downloads a malicious JS file:

Traffic Analysis

As we can see, the file is intentionally obfuscated in base64. The name of the file is ‘skqllz.ps1’.

Here is the end of the file:

Traffic Analysis

In this HTTP request, the host field is 5.252.153.241. The file is actually stored in benign domain: hosted-by.csrdp.host (5.252.153.241) which stores files on the cloud.

Looking at VirusTotal for the malicious host (5.252.153.241) we can see that its indeed malicious:

Traffic Analysis

We can see malicious “authenticatoor.org” domain:

Traffic Analysis

Conclusion & Answers

  • What is the IP address of the infected Windows client?
    • 10.1.17.215
  • What is the mac address of the infected Windows client?
    • *00:d0:b7:26:4a:74
  • What is the host name of the infected Windows client?
    • DESKTOP-L8C5GSJ
  • What is the user account name from the infected Windows client?
    • shutchenson
  • What is the likely domain name for the fake Google Authenticator page?
    • authenticatoor.org
  • What are the IP addresses used for C2 servers for this infection?
    • 5.252.153.241