BSides TLV CTF 2020 - Forensics

Isopach · June 30, 2020

I participated with CTF.SG again, but as most of us were burnt out from 0ctf, we didn’t have the full force this time around.

The site uses fixed scoring and not dynamic, so some questions were determined to be easier than others.


Check yourself so you won’t wreck yourself

Category: Forensics | 42 solves | 100 points

Challenge Description Dumbster diving. File Download Link

The challenge description mentions Dumpster, which means Garbage Bin - thus we check the Recycle Bin. When I first opened it, I saw many recycled phrases, like over 1000 files maybe, so I knew it was the right place. As we are searching for something that stands out, let’s sort by file type to filter out all these phrases.

Upon doing so, I found a very obvious BSIDESTLV2020.txt, which I opened and there was the flag!

Check Yourself Flag

FLAG BSIDESTLV{ICanSeeYouUnlessYouCleanUpAfterYourself}


Category: Forensics | 29 solves | 200 points

Challenge Description You need some EFF in your life. File Download Link

From what I can tell, EFF refers to Electronic Frontier Foundation, which doesn’t mean anything for us.

So what can be better with less, in a computer context? Maybe your browsing history?

Hence I went to check for browser history! First IE… nope nothing there.

So I continued looking for something that stood out… this time it was Chrome History!

Unfortunately I deleted the 8 GB image so I don’t have a screenshot now.

And we’ve found the flag!

FLAG BSIDESTLV2020{HideYourNeedleInTheHayStack}

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