Challenge list
CryptographyLevel 2★★☆☆☆Hash Length Extension Attack
Simple signatures such as hash(secret || message) can be vulnerable to length extension attacks with Merkle-Damgard…
CryptographyLevel 2★★☆☆☆Padding Oracle Basics
Padding oracle attacks use error differences as a plaintext recovery signal. This introductory task decodes leaked…
ProgrammingLevel 2★★☆☆☆Programming - Bash Job Log Analysis
/challenge/jobs.log is a nightly batch log that is regenerated with random data every time the container starts. Each…
ProgrammingLevel 2★★☆☆☆Programming - PIN Brute Force
/challenge/vault.json is a vault record that is regenerated with random data every time the container starts. It…
ProgrammingLevel 2★★☆☆☆Programming - Hash Verification and Decryption
Analyze the evidence file artifact-manifest.json, which is generated randomly at every start. Each artifact…
ProgrammingLevel 2★★☆☆☆Programming - Binary TLV Parsing
/challenge/capture.bin is a custom binary file that is regenerated with random data every time the container starts.…
CryptographyLevel 2★★☆☆☆Rainbow Table Attack
Unsalted fast password hashes can often be reversed with precomputed lookup databases. Reverse the given MD5 hash. MD5…
CryptographyLevel 2★★☆☆☆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.…
CryptographyLevel 2★★☆☆☆Predictable Randomness
Pseudo-random output with a fixed seed is reproducible and must not be used for cryptographic secrets. Flag generation…
CryptographyLevel 2★★☆☆☆Breaking Small RSA Keys
Factor a tiny RSA modulus, recover the private exponent, and decrypt a list of ciphertext values. Public key and…
CryptographyLevel 2★★☆☆☆Cryptanalysis - Breaking the Affine Cipher
ciphertext.txt is an English report encrypted with the affine cipher E(x) = (a*x + b) mod 26. Letter case is preserved…
ProgrammingLevel 2★★☆☆☆Regular Expressions - The One-Time Golden Glyph
Extract every KINO-four-digits-four-uppercase glyph from data.txt, identify the one occurring once, and submit it to…
LinuxLevel 3★★★☆☆Linux-Capabilities. Privilege Escalation Beyond SUID
A specific binary on this system has Linux capabilities assigned to it. Investigate a privilege escalation technique…
LinuxLevel 3★★★☆☆Linux-SUID Exploit. Escalating Privileges via the find Binary
A copy of the find command with the SUID bit set exists on this system. Use a well-known GTFOBins technique to obtain…
LinuxLevel 3★★★☆☆Linux-Proc Memory. Peeking at a Process's Environment
A daemon process runs continuously in the background, with the flag set as one of its environment variables.…
LinuxLevel 3★★★☆☆Linux-Strace. Tracing System Calls to Expose a File
A binary that leaves nothing in standard output or on disk is provided. It reads a key from a hidden file,…
LinuxLevel 3★★★☆☆Linux-Race Condition. Exploiting a TOCTOU Gap for Root Files
A cleanup script that root runs periodically has a gap (TOCTOU) between checking and acting on a file. Try exploiting…
ProgrammingLevel 3★★★☆☆Python Automation - SQLite Database Analysis
Examine data.db (SQLite: users / orders / audit_log), created at every start. Aggregate orders per user_id with…
ProgrammingLevel 3★★★☆☆Python Automation - Custom Cipher Decryption
cipher.txt holds the flag encrypted with a custom cipher (hex). Encryption applies per byte: add (key), xor…
ProgrammingLevel 3★★★☆☆Python Automation - Encrypted ZIP Password Cracking
A new /challenge/secret.zip is created at every start. It contains flag.txt and readme.txt, encrypted with ZipCrypto.…
ProgrammingLevel 3★★★☆☆Algorithms - BFS Shortest Path Through a Maze
Use BFS to find the shortest path from S to E in data.txt, then submit the UDLR move sequence to challenge.py. A…
ProgrammingLevel 3★★★☆☆Programming - SQLite Evidence Database
evidence.db is a SQLite database built from random data at every start (in /challenge, with the tables users /…
ProgrammingLevel 3★★★☆☆Programming - Web Scraping Graph Traversal
site.json is a crawl result built from random data at every start (in /challenge). It holds the start and target URLs…
ProgrammingLevel 3★★★☆☆Programming - ZIP Password Recovery
secret.zip is a ZIP encrypted with ZipCrypto (the traditional PKWARE cipher), created at every start (in /challenge,…