Freaks City

Binary Analyssi First, examine the binary with IDA Pro. The main function performs the following operations: int main() { char input[24]; char encrypted_flag[] = "rxusoCqxw{yqK`{KZqag{r`i"; printf("please input flag"); scanf("%24s", input); if(strlen(input) != 24) { printf(&quo ...

Low Public Exponent Attack When the public exponent $e$ is sufficiently small relative to the modulus $n$, and the padded plaintext satisfies $m^e < n$, the modular reduction becomes ineffective. In this scenario, the ciphertext $c$ is effectively an integer $e$-th power. By iterating through potential multiples of $n$ added to $c$, one can ...

Information Gathering web1 Viewing page source code reveals the flag. Right-click context menu or Ctrl+U keyboard shortcut provides access. web2 Direct browser DevTools access may be restricted. Alternative approaches include: Prefixing URL with view-source: Using Ctrl+U keyboard shortcut Opening DevTools via Ctrl+Shift+I Intercepting network ...

PHP applications often implement multilpe layers of security filters that require creative bypass techniques. This analysis examines various PHP filter evasion methods including URL encoding, newline injection, and request priority manipulation. Initial Code Analysis The target application begins with source code inspection: <?php highlight_ ...

Direct use echo with backticks. First ls, then tac to read the flag. Challenge 2 The filter is quite restrictive. One effective method is the character increment bypass. A small script can enumerate which characters are allowed: for ($c = 32; $c < 127; $c++) { if (!preg_match("/[a-zA-Z0-9@#%^&*:{}\-<\?>\"|`~\\\\]/&q ...

The challenge presents a web application with login and registration functionality. The objective is to retrieve the hidden flag from the database. Initial Exploration Upon accessing the application, we notice registration and login options. Attempting to register with the username "admin" reveals that the account already exists, sugg ...

Challenge 1: Magic Methods via Internal ClassesThe regex validation requires both parameters to contain alphabetic characters. The eval function executes the string as PHP code, where new $v1 instantiates a class named by the value of $v1, and ($v2()) invokes the function specified by $v2, passing its return value to the constructor.When an obj ...

Miscellaneous Who Am I? This challenge requires matching items against a provided list. While straightforward, it demands careful attention to detail as the information is spread across multiple entries. The solution involves cross-referencing each elemant systematically until all correspondences are established. You and Me Blind watermarking ...

Problem Overview The challenge provides two files: an APK and a pcapng packet capture. The solution requires analyzing network traffic and reverse engineering the encryption implementation. Traffic Analysis Opening the pcapng file reveals standard TCP traffic. Following TCP streams and decoding the hex content exposes the application protocol: ...

Challenge Overview The binary implements a flag verification mechanism using chained XOR operations. Understanding the execution order is critical: the program applies XOR transformations both before and after the main function executes, leveraging ELF initialization sections and exit handlers. ELF Initialization Function Table In ELF binarie ...