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I think some files in my system32 have been tampered with

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#1 comhall


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Posted 14 May 2011 - 03:11 PM

Hey Everyone!
I have recently had a huge trojan and adware and spyware problem. 12 hours of constant work later and I have it just about under control. I was reading online that a lot of malware hides in a file called wdmaud in system32. I read that if the owner doesn't say Microsoft Corporation in the details section that it is probably a fake. I have 5 different wdmaud files:

When I click into details on these files it says the owner name is TrustedInstaller and not Microsoft Corporation
This automatically makes it seem like a tampered with file. Especially the name TrustedInstaller makes it seem even more tampered with.
Posted Image
Everyone single one of my wdmaud files claims that the owner is TrustedInstaller.

Any advice would be really appreciated!
Thanks everyone

Edited by comhall, 14 May 2011 - 03:12 PM.

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#2 Broni


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Posted 14 May 2011 - 03:52 PM

If you're on Vista, or 7 TrustedInstaller is a legit service.

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#3 Didier Stevens

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Posted 16 May 2011 - 07:25 AM

Broni is right, this is normal on Windows Vista and 7.

You are confusing file ownership and application ownership.
TrustedInstaller is the owner of the file. When you read online that you should find Microsoft Corporation as the owner, they are not talking about file ownership, but about application ownership. Take an application like notepad.exe for example. Open its properties and look at the Details information (or Digital Signature if present), you'll see Microsoft Corporation.

Edited by Didier Stevens, 16 May 2011 - 07:39 AM.

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