302. Hunting for CVE-2025-59287 Exploitation

Hello everyone!

I think you already heard about a vulnerability in Microsoft's Windows Server Update Services (WSUS). Today we'll talk about Exploit Public-Facing Application (T1190) and CVE-2025-59287.

So, the vulnerability is already actively exploited ITW. According to this report, successful exploitation leads to spawning command and scripting interpreters from wsusservice.exe and w3wp.exe.

Here we have the first part of our detection opportunities. 

The first one:

event_type: "processcreatewin"

AND

proc_file_path: ("cmd.exe" OR "powershell.exe")

AND

proc_p_file_path: "wsusservice.exe"

The second:

event_type: "processcreatewin"

AND

proc_file_path: ("cmd.exe" OR "powershell.exe")

AND

proc_p_file_path: "w3wp.exe"

AND

proc_p_cmdline: "wsuspool"

Also, the adversary leveraged a PowerShell payload to exfiltrate data to a webhook.site endpoint. And this is another detection opportunity:

event_type: "dnsreqwin"

AND

dns_rname: "webhook.site"

AND

proc_file_path: "powershell.exe"

See you tomorrow!


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