Problems
Welcome to the Quantum Authentication System! This advanced system uses quantum-inspired cryptography with AES-CBC encryption …
One day, N fishermen (1 < N < 60) went fishing, and they caught X …
In how many ways can one white and one black knight be placed on a …
A web challenge that hides the flag on the server filesystem. The application exposes a …
You have intercepted a data line from an embedded device. The device communicates using a …
A small C program reads user input into a fixed-size buffer. There's a hidden win() …
A scrambled string was processed through several hidden transformation layers. Using the provided broken script, …
You are given a single image file named mysterious_landscape.png. Inspect it carefully and retrieve the …
You have intercepted a mysterious diagnostic interface exposed by a PS‑MicroX SoC development board. The …
We encrypted a secret flag with a custom keystream XOR. The keystream is generated by …
You are given a single standalone executable. When run, it prompts for a password. If …
DOCUMENT CODE: BR-79/RED/CONFIDENTIAL CLASSIFICATION: LEVEL 4 — UNAUTHORIZED POSSESSION IS A CRIME On October 12, …
You are given two matrices A and B, your task is to calculate the sum …
A friendly program wants to greet you… but its goodbye might say more than it …
You found a small program guarding a gate. When run, the program prompts: Enter the …
You are logged in as a guest, but there’s a special “admin dashboard.” The website …
The login form says: “SQL Injection is blocked!” But is it really? Find a way …
There is something hidden inside this image.
A small company reported suspicious activity on a development web service. The dev deployed a …
Provided is a compiled binary that prompts for a password. Reverse the binary to find …
You stand before a digital door that will only open for someone who knows the …
Find the full license plate number of the green bus that was traveling in the …
In the critical days leading up to a major cybersecurity competition, the development team at …
A flag was encrypted with a single-byte XOR and saved as hex. Recover the flag. …
Can you solve question by using TCP connection
An image containing a secret message (the flag) was encrypted using AES-128 in ECB mode. …
The website only shows a “Coming soon” page. But real CTF players know how to …
Your teammate accidentally uploaded the wrong file to the server. He claims: “The flag is …
A user goes by shadowfox92 across the web. Use open sources (GitHub, social media, pastebins) …
You intercepted a short message: EgdqatbHiprz{WTAAD_LDGAS} ProblemStack{******}