---
# System prepended metadata

title: USC 2024

---

# USC 2024

CTF Writeup for USC 2024 Challenge. I participated as "Rev" in the competition

|        Name        | Category | Solved? |
|:------------------:|:--------:|:-------:|
|     pineapple      | Forensic |   ✅    |
| Computer has virus | Forensic |   ✅    |
|    think_twice     | Forensic |   ✅    |
|      TommyCam      |  OSINT   |   ✅    |
|     beer sales     |  OSINT   |   ✅    |


# Forensic

## pineapple [300 Pts]

**Category:** Forensics

**Solves:** -

### Description
> Our covert pineapples intercepted this traffic from people at the convention. Try find out what was sent.
>
> The flag for this challenge will appear in the CYBORG{} flag format.

### Solution

Based on that description, we can try to figure out what is being sent by using the `stream` function in each protocol.

![image](https://hackmd.io/_uploads/B1TMlDgQJx.png)

We found something useful in this stream, namely:

`username=jbarker&filename=hoolicon&filepw=conjoined_TRIANGLES`

Apparently, there is a file called hoolicon somewhere inside this `pcapng` file.

We can try to dump all the media/files that are inside this `pcapng` file.

After dumping all the files, We found the file we're looking for in the name of `plans (1)`.

![image](https://hackmd.io/_uploads/SkjQePl7Jx.png)

Change the file extenstion to `.7z`

Extract the zip with `conjoined_TRIANGLES` as the password, and you got the flag

#### Flag

`CYBORG{pe4cefaRe_4x09}`

## Computer Has Virus [300 Pts]

**Category:** Forensics

**Solves:** -

### Description
> Help! I just fell victim to a phishing attack! I have attached the email they sent me. See if you can recover their secrets!

### Solution

We know that if we open the `URGENT.eml` file, we can find that there is an attachment named `antivirus.exe`.

We can try to extract the `.eml` file using `munpack` to get the file.

After getting `antivirus.exe`, we can try to examine the file using `strings` and find something interesting

```
!This program cannot be run in DOS mode.
JU$g
.text
`.rsrc
@.reloc
*b(!
*B(,
Yh}
1P      os
1&      os
$compressed = 'H4sIAAAAAAAA/1TNQWvyQBDG8Xs+xRgCrx4SFW+B8EJFtIcSMA1SSglxHZOlyW66+6xtEL97iVhpr8P8n19wbMqKEvKXLw/pdn3OFsKZOfoCtZm5qi7Svb1d5rZQMxSnhekLO7wtRhffC1gJSug16y24jXa8jzZAl0M2Ev1bHOemWSmhDzy+WhPyApSmYuSmGeAa6OLp1FkhcOSvo2xgSkitIqHb6f3A/4c6GTifPJiezh4RUWDYdlpZpoQe1Um/c7jj/ZY/HFtQmBtJv7zwiVHrA61Xz9d6ZyQ4TB06B/J/pmIKxvfdKEMJZ5f6wBOfvAuJEqK+6X/7fEPpZkSZbhm1VNU/S59Gq2o0dN53AAAA//+hRs8SawEAAA=='; $bytes = [System.Convert]::FromBase64String($compressed); $stream = New-Object IO.MemoryStream(, $bytes); $decompressed = New-Object IO.Compression.GzipStream($stream, [IO.Compression.CompressionMode]::Decompress); $reader = New-Object IO.StreamReader($decompressed); $obfuscated = $reader.ReadToEnd(); Invoke-Expression $obfuscated
BSJB
v4.0.30319
```

There are compressed variables that are in base64 format:

`H4sIAAAAAAAA/1TNQWvyQBDG8Xs+xRgCrx4SFW+B8EJFtIcSMA1SSglxHZOlyW66+6xtEL97iVhpr8P8n19wbMqKEvKXLw/pdn3OFsKZOfoCtZm5qi7Svb1d5rZQMxSnhekLO7wtRhffC1gJSug16y24jXa8jzZAl0M2Ev1bHOemWSmhDzy+WhPyApSmYuSmGeAa6OLp1FkhcOSvo2xgSkitIqHb6f3A/4c6GTifPJiezh4RUWDYdlpZpoQe1Um/c7jj/ZY/HFtQmBtJv7zwiVHrA61Xz9d6ZyQ4TB06B/J/pmIKxvfdKEMJZ5f6wBOfvAuJEqK+6X/7fEPpZkSZbhm1VNU/S59Gq2o0dN53AAAA//+hRs8SawEAAA==`

let's try again on CyberChef and see what we can find.

![image](https://hackmd.io/_uploads/Byc3bDxXyl.png)

#### Flag

`CYBORG{S3cur1ty_thr0ugh_Obscur1ty_1s_n0t_v3ry_s3cur3!}`

## think_twice [300 Pts]

**Category:** Forensics

**Solves:** -

### Description
> Think twice before you drive to the EXIT(F)!!!
> 
> Note: the flag format for this challenge is Cyb0rg{}, with a zero as the 0

### Solution

Image:



Based on the title of the image file, we can try to check the image metadata by using `exiftool`


```
┌──(rev㉿Prm)-[/mnt/c/Users/Indop/OneDrive/Documents/CTF/USC/2024/foren/think_twice]
└─$ exiftool metadata.png
ExifTool Version Number         : 12.76
File Name                       : metadata.png
Directory                       : .
File Size                       : 400 kB
File Modification Date/Time     : 2024:11:03 16:04:46+07:00
File Access Date/Time           : 2024:11:03 16:41:57+07:00
File Inode Change Date/Time     : 2024:11:03 16:05:59+07:00
File Permissions                : -rwxrwxrwx
File Type                       : JPEG
File Type Extension             : jpg
MIME Type                       : image/jpeg
Exif Byte Order                 : Big-endian (Motorola, MM)
Orientation                     : Horizontal (normal)
X Resolution                    : 144
Y Resolution                    : 144
Resolution Unit                 : inches
Software                        : UTNsaU1ISm5lMDFqUTJGeWRHaDVmU0E9
User Comment                    : Screenshot
Exif Image Width                : 1014
Exif Image Height               : 1162
Profile CMM Type                : Apple Computer Inc.
Profile Version                 : 2.1.0
Profile Class                   : Display Device Profile
Color Space Data                : RGB
Profile Connection Space        : XYZ
Profile Date Time               : 2024:03:29 00:41:41
Profile File Signature          : acsp
Primary Platform                : Apple Computer Inc.
CMM Flags                       : Not Embedded, Independent
Device Manufacturer             : Apple Computer Inc.
Device Model                    :
Device Attributes               : Reflective, Glossy, Positive, Color
Rendering Intent                : Perceptual
Connection Space Illuminant     : 0.9642 1 0.82491
Profile Creator                 : Apple Computer Inc.
Profile ID                      : 0
Profile Description             : Display
Profile Description ML (hr-HR)  : LCD u boji
Profile Description ML (ko-KR)  : 컬러 LCD
Profile Description ML (nb-NO)  : Farge-LCD
Profile Description ML (hu-HU)  : Színes LCD
Profile Description ML (cs-CZ)  : Barevný LCD
Profile Description ML (da-DK)  : LCD-farveskærm
Profile Description ML (nl-NL)  : Kleuren-LCD
Profile Description ML (fi-FI)  : Väri-LCD
Profile Description ML (it-IT)  : LCD a colori
Profile Description ML (es-ES)  : LCD a color
Profile Description ML (ro-RO)  : LCD color
Profile Description ML (fr-CA)  : ACL couleur
Profile Description ML (uk-UA)  : Кольоровий LCD
Profile Description ML (he-IL)  : ‏LCD צבעוני
Profile Description ML (zh-TW)  : 彩色LCD
Profile Description ML (vi-VN)  : LCD Màu
Profile Description ML (sk-SK)  : Farebný LCD
Profile Description ML (zh-CN)  : 彩色LCD
Profile Description ML (ru-RU)  : Цветной ЖК-дисплей
Profile Description ML (en-GB)  : Colour LCD
Profile Description ML (fr-FR)  : LCD couleur
Profile Description ML (hi-IN)  : रंगीन LCD
Profile Description ML (th-TH)  : LCD สี
Profile Description ML (ca-ES)  : LCD en color
Profile Description ML (en-AU)  : Colour LCD
Profile Description ML (es-XL)  : LCD color
Profile Description ML (de-DE)  : Farb-LCD
Profile Description ML          : Color LCD
Profile Description ML (pt-BR)  : LCD Colorido
Profile Description ML (pl-PL)  : Kolor LCD
Profile Description ML (el-GR)  : Έγχρωμη οθόνη LCD
Profile Description ML (sv-SE)  : Färg-LCD
Profile Description ML (tr-TR)  : Renkli LCD
Profile Description ML (pt-PT)  : LCD a cores
Profile Description ML (ja-JP)  : カラーLCD
Profile Copyright               : Copyright Apple Inc., 2024
Media White Point               : 0.95045 1 1.08905
Red Matrix Column               : 0.51512 0.2412 -0.00105
Green Matrix Column             : 0.29198 0.69225 0.04189
Blue Matrix Column              : 0.1571 0.06657 0.78407
Red Tone Reproduction Curve     : (Binary data 2060 bytes, use -b option to extract)
Video Card Gamma                : (Binary data 48 bytes, use -b option to extract)
Native Display Info             : (Binary data 62 bytes, use -b option to extract)
Make And Model                  : (Binary data 40 bytes, use -b option to extract)
Blue Tone Reproduction Curve    : (Binary data 2060 bytes, use -b option to extract)
Green Tone Reproduction Curve   : (Binary data 2060 bytes, use -b option to extract)
XMP Toolkit                     : Image::ExifTool 12.40
Image Width                     : 1014
Image Height                    : 1162
Encoding Process                : Baseline DCT, Huffman coding
Bits Per Sample                 : 8
Color Components                : 3
Y Cb Cr Sub Sampling            : YCbCr4:4:4 (1 1)
Image Size                      : 1014x1162
Megapixels                      : 1.2
```
Found something interesting in the `Software` value which is `UTNsaU1ISm5lMDFqUTJGeWRHaDVmU0E9`. We can try to decrypt it using CyberChef

![image](https://hackmd.io/_uploads/SJtWGDeQyl.png)

#### Flag

`Cyb0rg{McCarthy}`

# OSINT

## TommyCam [300 Pts]

**Category:** OSINT

**Solves:** -

### Description
> In May of 1995, university staff members completed what would become a quirky, well-enjoyed campus feature - TommyCam! The 24/7 live video feed of our unofficial mascot's statue, Tommy Trojan, is still going strong almost 30 years later.
>
> The site usc.edu was first archived by the Internet Archive in December 1996. At that time, the site included the technical specs for TommyCam. What PC was initially used to run TommyCam?
>
> Answers should be formatted like this, for example: CYBORG{ThinkPad T480}
>
> Note: this challenge is limited to 10 attempts to prevent brute-forcing

### Solution

We can use [web.archive.org](https://web.archive.org) to get the webpage in December 1996

![image](https://hackmd.io/_uploads/Hyi6fvgmkl.png)

The device PC is `Toshiba 5200 80386`

#### Flag

`CYBORG{Toshiba 5200 80386}`

## beer sales [300 Pts]

**Category:** OSINT

**Solves:** -

### Description
> In August 2024, a lot of beer was sold in Orlando, Florida. But how much, exactly? Lucky for us, they left the exact number on a PDF on an open FTP server! Include the total number of gallons of beer.
>
> For example: CYBORG{712931.12}
>
> UPDATE: Due to the FTP server going down, you may submit the URL of the PDF as the flag.
> 
> For example: CYBORG{example.com/dir/report.pdf}

### Solution
Because I solved this after the ftp is down, so the flag format will be the url of the pdf

![image](https://hackmd.io/_uploads/rJ-xmweX1l.png)

Because the link is URL Encoded format, we need to decode it first

![image](https://hackmd.io/_uploads/B18gmDxXJx.png)

the link is: 
`www.flgov.com/pub/llweb/Beer4.pdf`

#### Flag

`CYBORG{www.flgov.com/pub/llweb/Beer4.pdf}`