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NetSPI / PESecurity

PowerShell module to check if a Windows binary (EXE/DLL) has been compiled with ASLR, DEP, SafeSEH, StrongNaming, and Authenticode.
https://blog.netspi.com/verifying-aslr-dep-and-safeseh-with-powershell/
MIT License
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ASLR check should verify that the relocation table hasn't been stripped in EXE files #12

Closed wdormann closed 5 years ago

wdormann commented 5 years ago

Get-PESecurity indicates that EXE files use the ASLR mitigation solely upon the presence of it being linked with the /DYNAMICBASE flag. However, this is not enough for an EXE file to be randomized. If an EXE has its relocation table stripped, then it will not be randomized by windows.

In the case of vlc.exe, this tool indicates that it is ASLR compatible: vlc_mitigations

But the executable has its relocation table stripped, so it cannot be randomized using Windows ASLR: dynamicbase_reloc_pic

egru commented 5 years ago

Thanks for noticing that. I added a check and pushed it to the master branch 21d122f02b584d92fa665960c178f5be1277ccc8

wdormann commented 5 years ago

For the record, it appears that .NET executables are relocated on Windows 8 and newer even without a relocations table. So the check appears to get a little messier. I've updated https://gist.github.com/wdormann/dcdba9840701c879115f9aa5c1ef86dc to reflect this.

egru commented 5 years ago

Interesting. I'll take a look at it a bit more and add the checks in.

egru commented 5 years ago

I added checks for .NET and if the current Windows environment is 8 or greater.