Challenge list
Network SecurityLevel 2★★☆☆☆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 SecurityLevel 2★★☆☆☆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…
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…
Digital ForensicsLevel 2★★☆☆☆Find Password in Packet Capture
Clear-text HTTP traffic from a shop's internal network was captured. Among many requests, exactly one is the…
CryptographyLevel 2★★☆☆☆Padding Oracle Basics
Padding oracle attacks use error differences as a plaintext recovery signal. This introductory task decodes leaked…
Digital ForensicsLevel 2★★☆☆☆Identify Intrusion Time from File Timestamps
Analyze the modification times of the files in evidence/ to identify when the intrusion occurred and which hidden…
Digital ForensicsLevel 2★★☆☆☆Find Process in Memory Dump
memory.dump is a simplified text of memory-analysis output (pslist / psscan / cmdline). Find the suspicious process…
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…
Digital ForensicsLevel 2★★☆☆☆Recover Deleted Files
Recover the deleted compressed file (ZIP) from the disk image and find the flag in the memo inside it. Learn how to…
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…
Digital ForensicsLevel 2★★☆☆☆Message Hidden in Image LSB
Extract the message hidden in the LSB (Least Significant Bit) of a PNG file. Learn the basics of steganography…
Digital ForensicsLevel 3★★★☆☆Extract Session Cookies from Chrome
You are given `/challenge/Cookies` and `/challenge/History` (both SQLite) taken from a Linux Chrome profile. The…
Digital ForensicsLevel 3★★★☆☆Detect DNS Tunneling
Analyze the DNS query log `dns_queries.log` to detect data exfiltration via DNS tunneling. Find the host flooding a…
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…
Digital ForensicsLevel 3★★★☆☆Find Deleted File Traces in NTFS $MFT
You are given `/challenge/mft_records.txt`, the `$MFT` of the Windows machine `KINOCO-WS07` written out as per-record…
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…