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110 challenges (Page 2 of 5)

Digital ForensicsLevel 2★★☆☆☆

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…

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…

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.…

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…

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…

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…

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…

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…