Challenge list
Web SecurityLevel 2★★☆☆☆Web-17. Path Traversal in FileShare
FileShare lets users list and download files from a shared folder. Check whether the filename parameter passed to the…
Web SecurityLevel 2★★☆☆☆Web-18. XXE Attack via a Contact Form
This contact form serializes its input as XML and sends it to the server, which parses it and echoes the result.…
Web SecurityLevel 2★★☆☆☆Web-19. CSRF Transfer in a Banking App
This banking app lets a logged-in user transfer money. Check whether CSRF protections exist by seeing if a separate…
Web SecurityLevel 2★★☆☆☆Web-20. SSRF via the URL Fetcher
This URL Fetcher service retrieves and displays the content of any URL a user provides. Check whether it can be…
CryptographyLevel 2★★☆☆☆Finding Hash Collisions
MD5 collisions are practical. Hashes with broken collision resistance must not be used for security-sensitive…
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…
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…
Web SecurityLevel 3★★★☆☆Web-21. Blind Injection in Secure User Search
This user search app only reports whether a username exists, without showing direct query results. Investigate whether…
Web SecurityLevel 3★★★☆☆Web-22. CSP Bypass on the Secure Comment Board
This comment board is protected by a Content Security Policy restricting script execution to the site itself and a…
Web SecurityLevel 3★★★☆☆Web-23. Type Juggling in the Secure Authentication System
This login portal supports form login, a JSON API login, and a verification-code check. The admin account's real…
Web SecurityLevel 3★★★☆☆Web-24. Exploiting a Race Condition in Secure Bank
Secure Bank lets users spend a coin balance on shop prizes. If the balance check and the deduction happen as two…
Web SecurityLevel 3★★★☆☆Web-25. SSTI in the Greeting Card Generator
This greeting card generator is built with Flask/Jinja2 and renders the user's message directly through the template…
CryptographyLevel 3★★★☆☆Cryptanalysis - RSA Common Modulus Attack
Two systems reused the same RSA modulus n and only changed the public exponent. The ciphertexts c1 and c2 of the same…
CryptographyLevel 3★★★☆☆Cryptanalysis - Diffie-Hellman with a Small Prime
An old IoT device performed Diffie-Hellman key exchange with a prime p of only 36 bits. handshake.txt contains p, g, A…
Web SecurityLevel 4★★★★☆Web-26. Prototype Pollution in User Profile Manager
In this Node.js/Express app, a logged-in user can update their own profile. Check whether the recursive merge function…
Web SecurityLevel 4★★★★☆Web-27. GraphQL Introspection Leak
This GraphQL API exposes a schema of User objects with introspection enabled. Investigate whether undocumented queries…
Web SecurityLevel 4★★★★☆Web-28. Hijacking an OAuth Authorization Code
This OAuth 2.0 authorization provider offers a login flow, but its redirect_uri validation may be weak. Investigate…
Web SecurityLevel 4★★★★☆Web-29. NoSQL Injection in a MongoDB Login Form
This login portal is backed by MongoDB and builds its query directly from raw JSON username/password input.…
Web SecurityLevel 4★★★★☆Web-30. Insecure Deserialization in KinoVault
A legacy backup system codenamed KinoVault reportedly serializes user session objects with Python's pickle module and…