# Ricerca CTF 2023 - Backup Sheet

***This is an emergency handout that is distributed to players in case the score server is down.***

## Welcome

### welcome

Tags: `welcome` `warmup`
Description:
> Welcome to Ricerca CTF 2023! To find the flag for this challenge:
> 1. Read the <a href="https://ricerca-ctf-2023-dev.web.app/rules" target="_blank">rule</a>.</li>
> 2. Find the flag in <code>#announcement</code> channel in Discord.</li>

## Web

### Cat Café
Files: [cat-cafe.zip](https://mega.nz/file/J4chBQxL#BVYuR--uVT9ebUDEol5mq4ERsa1RVyCmUM34TKfycr4)
Server:
- main: http://cat-cafe.2023.ricercactf.com:8000/
- backup: http://backup-web.2023.ricercactf.com:8000/

Tags: `web` `warmup` `author:ptr-yudai`
Description:
> Which cat do you like the most?

### tinyDB
Files: [tinydb.zip](https://mega.nz/file/140m2RgJ#Wj-DCGh-Nq-PoaNtVVBdoVJh0uxQ7Rh_QzrN_NDI_Fc)
Server:
- main: http://tinydb.2023.ricercactf.com:8888/
- backup: http://backup-web.2023.ricercactf.com:8888/

Tags: `web` `author:xryuseix`
Description:
> It's a tiny tiny user database...

### funnylfi
Files: [funnylfi.zip](https://mega.nz/file/k8cWxBJS#q9u7MyxggDQZFx8g_ZR9F60pLCsR5T8LjOdVg4Y84ko)
Server:
- main: http://funnylfi.2023.ricercactf.com:31415/
- backup: http://backup-web.2023.ricercactf.com:31415/

Tags: `web` `author:satoki`
Description:
> A super-secure website viewer on a website.

### ps converter
Files: [ps-converter.zip](https://mega.nz/file/V0lyhRoC#iAOmrnW0o8AAPk5FOZMonqDt-w3dUGYXDiYYfa_dO-A)
Server:
- main: http://ps-converter.2023.ricercactf.com:51514/
- backup: http://backup-web.2023.ricercactf.com:51514/

Tags: `web` `author:hugeh0ge`
Description:
> Try my Postscript converter!

## Crypto

### Revolving Letters
Files: [revolving-letters.zip](https://mega.nz/file/dg0E1ZAK#yeP4MxFL3jIZh7QsIa7EBwUN_HH2VdyQ4xUkXOniQaA)
Tags: `crypto` `warmup` `author:keymoon`
Description:
> Who keeps spinning letters around?

### Rotated Secret Analysis
Files: [rotated-secret-analysis.zip](https://mega.nz/file/kwF3yDrB#LcErXt8I7QKdfQnzogvuCGH1AOrIiB0yqdqJZL46dEE)
Tags: `crypto` `author:keymoon`
Description:
> A wise person once said that rotating the secret makes it safer!
> Huh? Isn't that what they meant?

### RSALCG
Files: [rsalcg.zip](https://mega.nz/file/B4MGXADD#sOfy1QjkM6DpVJtAxwhdTC_J4Q5QZ8uJrOf06NKILdI)
Tags: `crypto` `author:ptr-yudai`
Description:
> LCG is weak, but what if it's used with RSA?

### dice-vs-kymn
Files: [dice-vs-kymn.zip](https://mega.nz/file/B1shGbYa#w2UN-XvoHQ4fHPUaMqRedoaArZ9gkokq197wRj5ZDRk)
Server:
- main: `nc dice-vs-kymn.2023.ricercactf.com 5963`
- backup: `nc backup-other.2023.ricercactf.com 5963`

Tags: `crypto` `author:ptr-yudai` `author:keymoon`
Description:
> [HELP WANTED] King Dice

## Pwn

### BOFSec
Files: [bofsec.zip](https://mega.nz/file/t50nCSTD#dz3Lq8DCfJ7kTUvmfOIHWuuWZBvifzj5pH3G-3r9fY4)
Server:
- main: `nc bofsec.2023.ricercactf.com 9001`
- backup: `nc backup-pwn.2023.ricercactf.com 9001`

Tags: `pwn` `warmup` `author:ptr-yudai`
Description:
> 100% authentic

### NEMU
Files: [nemu.zip](https://mega.nz/file/Rg93zSCJ#Cal86-uvFdgPVMn_Uu4ot4ScF-OchLceyZlCPqS-_UA)
Server:
- main: `nc nemu.2023.ricercactf.com 9002`
- backup: `nc backup-pwn.2023.ricercactf.com 9002`

Tags: `pwn` `author:keymoon`
Description:
> I could only implement a few instructions.
> That's because I was sleepy.

### safe thread
Files: [safe-thread.zip](https://mega.nz/file/Q0FQkL6I#3Y8Q-5Lw0JcpqPcJlz_gssl-_wnnvcOryoK41OdHnoo)
Server:
- main: `nc safe-thread.2023.ricercactf.com 9004`
- backup: `nc backup-pwn.2023.ricercactf.com 9004`

Tags: `pwn` `author:ptr-yudai`
Description:
> Okay, BOF is useless now.

### Oath to Order
Files: [oath-to-order.zip](https://mega.nz/file/I9twGLDY#NTU4M1JOM_P7XomMrJ3oraHPai6KD0PtGQf0k-19hGI)
Server:
- main: `nc oath-to-order.2023.ricercactf.com 9003`
- backup: `nc backup-pwn.2023.ricercactf.com 9003`

Tags: `pwn` `author:keymoon` `author:ptr-yudai`
Description:
> Take care of the order.

## Reversing

### crackme
Files: [crackme.zip](https://mega.nz/file/9gEiHa4L#vx4w8uvLZx_oarHq1c1K8LSaCEl_siN0EnXgACQHjJI)
Tags: `reversing` `warmup` `author:ptr-yudai`
Description:
> Can you crack the password?

### ignition
Files: [ignition.zip](https://mega.nz/file/hstwSDxS#51n4UVJ8ejyzHosQPJzK5gahMwy0f2WXQLVjgl9riWw)
Tags: `reversing` `author:Arata`
Description:
> 3... 2... 1... ignition.
> Hint: use Ghidra v9.2.2

### tic tac toe?
Files: [tic-tac-toe.zip](https://mega.nz/file/5p1STRxR#fTU_4wgyUQ-B6K1vv7HoyNPf5ajAa9jMHuvpPNMfHdM)
Tags: `reversing` `author:Arata`
Description:
> I downloaded a game from the ancient internet, but it seems buggy...?

### RSLocker
Files: [rslocker.zip](https://mega.nz/file/I9NgSIhC#WIgifQRkWaRqJU4mmTz4VrY5hxmPXlJBIrt6WJ5l8Hg)
Tags: `reversing` `author:ptr-yudai`
Description:
> A ransomware is spreading around the world.
> We successfully extracted the screen locker of the malware.
> Would you help us find the unlock code?
> <small style="color:red;">* The program may contain some malicious codes. Do not run it unless you understand its behavior.</small>

## Forensics

### My name is Power!
Files:
- Google Drive: [memory.zip](https://drive.google.com/file/d/15oALs514gxEqirU-tqYvpK9Q0aQGR3of/view?usp=share_link)
- MEGA Drive: [memory.zip](https://mega.nz/file/1wcknbaL#Xnfw3E9D7TcsttJr0AC8cWHYtBuFleet8P82Nb67BG4)

Tags: `forensics` `author:pinksawtooth`
Description:
> Show me your Power!

## Misc

### gatekeeper
Files: [gatekeeper.zip](https://mega.nz/file/1tEiTSJS#9pyKWgvDDXaL1z1JvzZJhJtSsdKIRvwUwn46pXYuYmA)
Server:
- main: `nc gatekeeper.2023.ricercactf.com 10005`
- backup: `nc backup-other.2023.ricercactf.com 10005`

Tags: `misc` `author:Arata`
Description:
> Bypass the base64 filter