Tags: prefetch forensic 

Rating:

Fetch

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For this challenge we get a file I haven't seen before. A Windows imaging image:

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After some research with Google, we find that there are tools we can use to parse these in Linux and in Windows. Initially I install wimtools.

sudo apt-get install wimtools

After that I mounted it to a folder and found a bunch of prefetch files:

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I read some articles trying to find some easy ways of parsing the information in these files as there were quite a few, a real "needle in a haystack" situation.

https://www.hackingarticles.in/forensic-investigation-prefetch-file/

Eventually I found this Windows tool as it was easier for me to have a GUI in this instance: https://www.nirsoft.net/utils/win_prefetch_view.html

My aim was to look into the prefetch files of stuff that had user input like, notepad, cmd, powershell and eventually I found wordpad:

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I used cyberchef to quickly convert it to lowercase:

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Original writeup (https://github.com/LazyTitan33/CTF-Writeups/blob/main/Nahamcon2023/Forensics/Fetch.md).