feat: added UMass CTF 2023

README.md

@@ -31,4 +31,5 @@ List of CTF events that i have joined before
 | b01lers CTF 2023 | 18 March, 05:00 WIB — 20 March 2023, 05:00 WIB | [Link](/b01lers%20CTF%202023/) |
 | OmWars CTF 2023 Quals | 18 March, 13:00 WIB — 19 March 2023, 01:00 WIB | [Link](/OmWars%20CTF%202023%20Quals/)
 | Cyber Apocalypse 2023: The Cursed Mission | 18 March, 20:00 WIB — 23 March 2023, 19:59 WIB | [Link](/Cyber%20Apocalypse%202023%20The%20Cursed%20Mission/) |
-| LINE CTF 2023 | 25 March, 07:00 WIB — 26 March 2023, 07:00 WIB | [Link](/LINE%20CTF%202023/)
+| LINE CTF 2023 | 25 March, 07:00 WIB — 26 March 2023, 07:00 WIB | [Link](/LINE%20CTF%202023/)
+| UMass CTF 2023 | 25 March, 06:00 WIB — 27 March 2023, 00:00 WIB | [Link](/UMass%20CTF%202023/)

UMass CTF 2023/Deepfried/README.md

@@ -0,0 +1,42 @@
+# Deepfried
+> `-`
+
+## About the Challenge
+We have been given a source code (You can download the file [here](DeepFried.zip))
+
+![preview](images/preview.png)
+
+## How to Solve?
+If we check the the source code, we will see there is a folder called `restriced_memes` and inside the folder there is an image called `TheFlag.jpg` so I'm assumming we need to access `/restricted_memes/TheFlag.jpg` to obtain the flag
+
+![TheFlag](images/TheFlag_Image.png)
+
+But we can't access that endpoint directly because that endpoint can only be accessed locally.
+
+```javascript
+router.all('/restricted_memes/:img', async (req,res, next)=>{
+    if(req.ip === '::ffff:127.0.0.1') {
+        next();
+    } else {
+       return res.status(403).send("Unauthorized Request");
+    }
+})
+```
+
+So, the idea here. We need to input `http://127.0.0.1:3000/restricted_memes/TheFlag.jpg` in the `Image URL` form
+
+![TheFlag](images/TheFlag.png)
+
+As we can see in the image, the flag was located in `flag.txt` directory. So we need to input `http://127.0.0.1:3000/restricted_memes/flag.txt` in the `Image URL` form
+
+![preview_flag](images/preview_flag.png)
+
+Press `CTRL + U` to check the source code
+
+![flag](images/flag.png)
+
+You will see there is a Base64 string in `img` tag. Decode the msg using `Base64` Decoder to obtain the flag
+
+```
+UMASS{v@Mo$_APr0nTaR_1!i!I!}
+```

UMass CTF 2023/README.md

@@ -0,0 +1,8 @@
+# UMass CTF 2023
+CTF writeup for The UMass CTF 2023. I took part in this CTF competition with the TCP1P team, and got 15th place out of 571 teams
+
+Thanks to the team especially @dimasma0305
+
+| Category | Challenge |
+| --- | --- |
+| Web | [Deepfried](/UMass%20CTF%202023/Deepfried/)