Challenge list
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…
LinuxLevel 4★★★★☆Linux-Kernel Module. Gaining Root via a Vulnerable Driver
This challenge analyzes a vulnerable character-device driver as a safe user-space simulation. No real kernel module is…
LinuxLevel 4★★★★☆Linux-Buffer Overflow. Exploiting a gets() Vulnerability
A vulnerable SUID C binary with protections disabled is provided. Exploit its buffer overflow to redirect control flow…
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…
CryptographyLevel 4★★★★☆Cryptanalysis - DSA Nonce Reuse Key Recovery
/challenge/signatures.json, created with fresh keys at every start, holds the DSA public parameters (p of 1024 bits, q…
CryptographyLevel 4★★★★☆Cryptanalysis - Wiener's Attack on RSA
An embedded-device team made the RSA private exponent d very small to speed up decryption. The public exponent e in…
CryptographyLevel 4★★★★☆Cryptanalysis - Recovering an LCG's Hidden Parameters
A service generated both session tokens and an encryption keystream from a linear congruential generator x_{k+1} =…
LinuxLevel 5★★★★★Linux-eBPF Rootkit. Unmasking a Hidden Process
This challenge safely recreates eBPF-rootkit investigation as offline evidence analysis. Without loading eBPF, tell…
LinuxLevel 5★★★★★Linux-Kernel Exploit. Rewriting a Read-Only File with Dirty COW
This challenge models mmap, MAP_PRIVATE, and madvise—the ingredients used by Dirty COW (CVE-2016-5195)—as a safe,…
CryptographyLevel 5★★★★★Cryptanalysis - RSA e=3 Broadcast Attack
broadcast.json contains the same plaintext encrypted with unpadded RSA e=3 under three pairwise-coprime moduli.…