Cybersecurity CTF challenges

Choose a domain and difficulty, inspect the evidence, and verify each conclusion in a safe environment.

Programming Level 3

Programming - Packet Log Analysis

capture.txt is generated from the FLAG injected at startup. Select flow=exfil payload_hex and XOR-decrypt with 0x5A to…

Programming Level 3

Programming - Multithreaded Result Reassembly

worker-results.jsonl is generated from the FLAG injected at startup. Base64-decode results, XOR with worker SHA-1, and…

Programming Level 3

Programming - Memory Dump Analysis

memory.img is generated from the FLAG injected at startup. Extract the ALLOC:0x4040 little-endian region and…

Programming Level 3

Programming - Known-Plaintext Attack

known.txt and ciphertext.b64 are generated from the FLAG injected at startup. Derive the repeating XOR keystream from…

Programming Level 3

Programming - Custom Protocol Parsing

protocol.bin is generated from the FLAG injected at startup. Walk length-prefixed KINO frames and XOR-decrypt type=3…

Programming Level 3

Programming - Image Steganography

image.pgm is generated from the FLAG injected at startup. Read pixel LSBs in 8-bit groups until NUL to recover the flag.

Forensics Level 3

Find Suspicious Network Connections in Memory

Analyze the network-connection record `netstat_dump.txt` to identify the suspicious C&C connection. The single…

Forensics Level 3

Recover Executed Commands from Memory

Analyze the memory-string record `memdump.txt` to recover the executed command history. Decode the Base64 strings and…

Forensics Level 3

Recover Deleted SQLite Records

Recover the deleted record from the SQLite database `app.db` to obtain the flag. Deleted rows persist in the freelist,…

Forensics Level 3

Decompress Multi-Layer Archive

Decompress a file that has been compressed multiple times with different formats (zip, tar, gzip, bzip2). Learn to…

Forensics Level 3

Decrypt Encrypted Disk

`secret_disk.img` is a genuine LUKS2 container. Brute-force `wordlist.txt` to find the weak passphrase, then decrypt…

General Skills Level 3

Regex Expert - Data Validation

/app/data.txt contains various data formats. Extract lines that satisfy ALL conditions: 1. Contains email format…

Forensics Level 3

Data Hidden in Audio File

`hidden.wav` hides a message encoded with on-off keying (OOK). Turn the tone on/off slots into bits and decode them to…

General Skills Level 3

Advanced Automation - Directory Monitor

`/challenge/logs/` holds a large set of access logs. Aggregate status-404 requests per source IP and identify the…

General Skills Level 4

AWS CLI - S3 Bucket Investigation

Analyze the S3 configuration audit under `/challenge/s3_audit/`. Inspect each bucket's `*_acl.json`, `*_policy.json`,…

Forensics Level 4

Extract Secret Key from Android App

Extract a safe ZIP-formatted APK fixture and analyze the API secret recorded in its Android resources. No real device…

General Skills Level 4

Ansible Automation - Server Configuration Management

Analyze a generated vault export without running Ansible or touching a server. Recover the encoded payload recorded…

General Skills Level 4

CI/CD Security - GitHub Actions Vulnerability

Investigate the GitHub Actions workflows under `/challenge/repo/.github/workflows/` and the run logs under…

Forensics Level 4

Detect Unauthorized Access in CloudTrail Logs

Analyze AWS CloudTrail logs to detect unauthorized IAM access and data exfiltration. Learn cloud forensics. Provided…

Forensics Level 4

Extract Secrets from Docker Image Layers

The startup-generated `image/` directory is a `docker save`-style image layer layout. Analyze its `layer.tar` files…

General Skills Level 4

Infrastructure as Code - Terraform Security

Analyze a generated tfstate artifact without initializing a Terraform provider. Recover the flag from the audit_only…

General Skills Level 4

Kubernetes Basics - Cluster Investigation

Investigate a Pod snapshot artifact without connecting to a Kubernetes cluster. Recover the encoded value in the…

Linux Level 4

Linux-Kernel Module. Gaining Root via a Vulnerable Driver

This challenge analyzes a vulnerable kernel module with a /proc interface as a safe user-space simulation. Find the…

Linux Level 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…