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Competition writeups, grouped by event. Each one walks through the full solve.

14 writeups5 events

Securinets Quals 2026

Oct 2026 4 challenges Event overview

  1. 01 Silent Tone Three radio transmitters talk over each other on one 433 MHz channel. Read the protocol out of a USB log, repair a logic-analyser recording that silently dropped samples, decode the loud decoy, subtract it, and peel the two quiet transmitters apart to rebuild an encrypted flag. Hard 35 min
  2. 02 dumppwn A Windows 11 memory dump caught one second after a kernel exploit ran. Convert the unusual RDMP dump format, spot a fake system process, read its XOR key out of the binary, and decrypt a secret straight out of physical memory, while ten AI-bait decoy flags try to pull you off course. Medium 16 min
  3. 03 Gelatino A layered disk-forensics challenge: identify a replaced UEFI loader, reverse its custom byte decoder, turn the recovered shop records into a LUKS passphrase, and decrypt the final OpenSSL recipe. Hard 18 min
  4. 04 Dijavou A 27-answer incident-response investigation that follows a Tomcat compromise through sudo privilege escalation, cron persistence, an obfuscated encryptor, ICMP exfiltration, and IoT malware. Hard 15 min

Friendly Securinets CTF 2026

Sep 2026 5 challenges Event overview

  1. 01 Forensics Wave 1 Seven easy-to-medium forensics challenges: header repair, layered encodings, nested archives, a disguised shell archive, low-contrast stego, Morse audio, and a PNG/PDF polyglot. Easy 13 min
  2. 02 Forensics Wave 2 Eighteen intermediate forensics tasks covering Git history, browser artifacts, DNS, maldocs, packet analysis, steganography, and reverse engineering. Medium 34 min
  3. 03 Forensics Wave 3 Fourteen advanced forensics challenges spanning memory analysis, DFIR, TLS recovery, cloud logs, mobile artifacts, network cryptanalysis, and hardware signals. Hard 49 min
  4. 04 Twofold A Windows reverse-engineering challenge that requires recovering a license key statically, then manipulating execution in a debugger to reveal a runtime-only unlock token. Hard 6 min
  5. 05 Reset Vault A web exploitation challenge built around predictable MongoDB ObjectIds, deterministic token generation, and AES keys derived from attacker-guessable identifiers. Medium 14 min

Cybertek CTF

Apr 2026 1 challenge

  1. 01 Malsou9a Full analysis of a .NET malware implant found in a memory dump — from DLL extraction and AES key recovery to C2 communication, PDF payload analysis, and JavaScript deobfuscation to retrieve the flag from Azure Blob Storage. Hard 7 min

Securinets CTF Quals 2025

Feb 2025 3 challenges Event overview

  1. 01 Silent Visitor Investigation of a malicious npm package and its Go-based payload through Windows disk image analysis. Medium 3 min
  2. 02 Lost File Ransomware-style challenge requiring memory capture analysis and reverse engineering of an encryption tool to recover a deleted key. Hard 3 min
  3. 03 Recovery Analysis of a DNS-based covert channel used for data exfiltration and ransomware delivery. Includes malware reconstruction and custom LCG decryption. Hard 2 min

QnQSec CTF 2025

Jan 2025 1 challenge Event overview

  1. 01 Masks Tracing a phishing attack chain from initial email delivery in Outlook to scheduled task persistence using Volatility 3 and AmCache forensics. Medium 2 min