Challenge list
AES-ECB Mode Weakness
ECB leaks repeated block patterns. This introductory task first checks the difference between encryption and encoding.…
Find Attack in Apache Logs
Analyze the Apache access.log (common format) to find traces of SQL injection. Tell which attacks succeeded and which…
Flag Hidden in Excel Macro
Analyze the macro code embedded in the Excel workbook and find the hidden authentication code (the flag). Learn how to…
Hidden PDF Streams
The PDF file contains compressed object streams. An internal note that is not shown on the page is hidden inside them.…
RC4 Stream Cipher Weakness
RC4 was once widely used but is now deprecated. This introductory task focuses on recognizing the provided data…
Vigenere Cipher Decryption
Decrypt a Vigenere cipher when the key length is known and retrieve the flag. Ciphertext:…
Find USB History in Windows Registry
Analyze the SYSTEM file (a text model of the USBSTOR part of the registry hive) to identify the USB device that was…
Find Secret File in Disk Image
Inspect the ext4 filesystem disk image `disk.img`, find the secret backup hidden in the filesystem, and recover the…
Network Analysis - DNS Zone Transfer Leak
An unauthenticated DNS zone transfer (AXFR) against a misconfigured authoritative server was captured. Download the…
Network Analysis - ICMP Data Exfiltration
Data was exfiltrated from the internal host 10.20.0.15 to the external host 203.0.113.66 disguised as ping (ICMP echo…
Network Analysis - SMB Share Enumeration Leak
An attacker enumerating SMB shares on the network was captured. Download the packet capture (traffic.pcap), follow the…
Network Analysis - Telnet Credentials
A legacy server was administered over Telnet in clear text. Download the packet capture (traffic.pcap), follow the…
Network Analysis - Anonymous FTP Transfer
An anonymous FTP session was captured in clear text. Download the packet capture (traffic.pcap), follow the FTP data…
Network Analysis - Clear-text HTTP Credentials
Analyze traffic intercepted on public Wi-Fi where someone logged in over plain HTTP. Download the packet capture…
Network Analysis - Plaintext SMTP Attachment
The internal host 10.30.0.25 sent an email to port 25 of the mail server 10.30.0.10 without encryption. Download…
Finding Hash Collisions
MD5 collisions are practical. Hashes with broken collision resistance must not be used for security-sensitive…
Hash Length Extension Attack
Simple signatures such as hash(secret || message) can be vulnerable to length extension attacks with Merkle-Damgard…
Find Password in Packet Capture
Clear-text HTTP traffic from a shop's internal network was captured. Among many requests, exactly one is the…
Padding Oracle Basics
Padding oracle attacks use error differences as a plaintext recovery signal. This introductory task decodes leaked…
Identify Intrusion Time from File Timestamps
Analyze the modification times of the files in evidence/ to identify when the intrusion occurred and which hidden…
Find Process in Memory Dump
memory.dump is a simplified text of memory-analysis output (pslist / psscan / cmdline). Find the suspicious process…
Rainbow Table Attack
Unsalted fast password hashes can often be reversed with precomputed lookup databases. Reverse the given MD5 hash. MD5…
One-Time Pad Key Reuse Attack
A one-time pad is safe only when the key is used once. Reusing the key lets known plaintext recover other plaintexts.…
Predictable Randomness
Pseudo-random output with a fixed seed is reproducible and must not be used for cryptographic secrets. Flag generation…