# Elijah's CTF Blog

## Elijah's CTF Blog

- [Home](https://elijahchia.gitbook.io/ctf-blog/home.md): Hello!
- [Cyber SEA Games 2025](https://elijahchia.gitbook.io/ctf-blog/cyber-sea-games-2025.md)
- [Sierra Leone - Simple Forensic (forens)](https://elijahchia.gitbook.io/ctf-blog/cyber-sea-games-2025/sierra-leone-simple-forensic-forens.md)
- [India - Reverse Me & Extract Flag from Packets (rev/network)](https://elijahchia.gitbook.io/ctf-blog/cyber-sea-games-2025/india-reverse-me-and-extract-flag-from-packets-rev-network.md)
- [Brazil - SMB3overKerberos (network)](https://elijahchia.gitbook.io/ctf-blog/cyber-sea-games-2025/brazil-smb3overkerberos-network.md)
- [South Sudan - Decode the RFID Tag (rev)](https://elijahchia.gitbook.io/ctf-blog/cyber-sea-games-2025/south-sudan-decode-the-rfid-tag-rev.md)
- [Switzerland - Relayed and Betrayed (network)](https://elijahchia.gitbook.io/ctf-blog/cyber-sea-games-2025/switzerland-relayed-and-betrayed-network.md)
- [Italy - Silent Signals (network)](https://elijahchia.gitbook.io/ctf-blog/cyber-sea-games-2025/italy-silent-signals-network.md)
- [New Zealand - Passport (forens)](https://elijahchia.gitbook.io/ctf-blog/cyber-sea-games-2025/new-zealand-passport-forens.md)
- [TISC 25](https://elijahchia.gitbook.io/ctf-blog/tisc-25.md)
- [Level 1 - Target Reference Point (OSINT)](https://elijahchia.gitbook.io/ctf-blog/tisc-25/level-1-target-reference-point-osint.md)
- [Level 2 - The Spectrecular Bot (AI)](https://elijahchia.gitbook.io/ctf-blog/tisc-25/level-2-the-spectrecular-bot-ai.md)
- [Level 3 - Rotary Precision (Misc)](https://elijahchia.gitbook.io/ctf-blog/tisc-25/level-3-rotary-precision-misc.md)
- [Level 4 - Spectre Memory (AI)](https://elijahchia.gitbook.io/ctf-blog/tisc-25/level-4-spectre-memory-ai.md)
- [Level 5 - Syntra (rev)](https://elijahchia.gitbook.io/ctf-blog/tisc-25/level-5-syntra-rev.md)
- [Level 6 - Passkey (web)](https://elijahchia.gitbook.io/ctf-blog/tisc-25/level-6-passkey-web.md)
- [Level 7B - Signull (mobile / web)](https://elijahchia.gitbook.io/ctf-blog/tisc-25/level-7b-signull-mobile-web.md)
- [Level 8B - Super "Optimised" Swap (SpiderMonkey pwn)](https://elijahchia.gitbook.io/ctf-blog/tisc-25/level-8b-super-optimised-swap-spidermonkey-pwn.md)
- [Level 9 - HWisntThatHardv2 (hardware pwn)](https://elijahchia.gitbook.io/ctf-blog/tisc-25/level-9-hwisntthathardv2-hardware-pwn.md)
- [Level 10 - Countle Secured Storage (web)](https://elijahchia.gitbook.io/ctf-blog/tisc-25/level-10-countle-secured-storage-web.md)
- [Star Labs Summer Pwnables 2025](https://elijahchia.gitbook.io/ctf-blog/star-labs-summer-pwnables-2025.md): This was a small pure-pwn ctf which started on August 18, 2025
- [Level 2 - not quite baby kernel (linux kernel pwn)](https://elijahchia.gitbook.io/ctf-blog/star-labs-summer-pwnables-2025/level-2-not-quite-baby-kernel-linux-kernel-pwn.md): Linux kernel heap pwn
- [SFF CTF 25](https://elijahchia.gitbook.io/ctf-blog/sff-ctf-25.md): SkillsFuture CTF 2025 - Forensics-style kind of CTF Challenges
- [SSMCTF 25](https://elijahchia.gitbook.io/ctf-blog/ssmctf-25.md): Played as open team (no prizes) as G04T3DP30PL3
- [Orange Deportation Simulator (pwn)](https://elijahchia.gitbook.io/ctf-blog/ssmctf-25/orange-deportation-simulator-pwn.md): MAKE FLAGS GREAT AGAIN! HELP ME DEPORT THE ORANGES!
- [ecssp (crypto)](https://elijahchia.gitbook.io/ctf-blog/ssmctf-25/ecssp-crypto.md): The Merkle-Hellman cryptosystem is broken, but what if I use it over elliptic curves?
- [x3ctf25](https://elijahchia.gitbook.io/ctf-blog/x3ctf25.md)
- [notcrypto (rev)](https://elijahchia.gitbook.io/ctf-blog/x3ctf25/notcrypto-rev.md)
- [pickle-season (rev)](https://elijahchia.gitbook.io/ctf-blog/x3ctf25/pickle-season-rev.md)
- [devnull-as-a-service (pwn)](https://elijahchia.gitbook.io/ctf-blog/x3ctf25/devnull-as-a-service-pwn.md)
- [Wargames.MY CTF 2024](https://elijahchia.gitbook.io/ctf-blog/wargames.my-ctf-2024.md): This CTF took place from Sat, 28 Dec. 2024, 00:00 SGT — Sun, 29 Dec. 2024, 00:00 SGT. My team, NUS Greyhats, emerged 1st place with 15121 points. I helped to solve 4 crypto and 1 rev challenge.
- [Credentials (crypto)](https://elijahchia.gitbook.io/ctf-blog/wargames.my-ctf-2024/credentials-crypto.md)
- [Stones (rev)](https://elijahchia.gitbook.io/ctf-blog/wargames.my-ctf-2024/stones-rev.md)
- [Rick'S Algorithm (crypto)](https://elijahchia.gitbook.io/ctf-blog/wargames.my-ctf-2024/ricks-algorithm-crypto.md)
- [Rick'S Algorithm 2 (crypto)](https://elijahchia.gitbook.io/ctf-blog/wargames.my-ctf-2024/ricks-algorithm-2-crypto.md)
- [Hohoho 3 continue (crypto)](https://elijahchia.gitbook.io/ctf-blog/wargames.my-ctf-2024/hohoho-3-continue-crypto.md)
- [Advent of CTF 2024](https://elijahchia.gitbook.io/ctf-blog/advent-of-ctf-2024.md): Advent of CTF 2024 is a beginner-oriented CTF running from 1st to 25th December, with a challenge being released every day. We had until the last day of the year to submit our flags!
- [Jingle Bell ROP (pwn)](https://elijahchia.gitbook.io/ctf-blog/advent-of-ctf-2024/jingle-bell-rop-pwn.md): A classic ROP challenge
- [help (pwn)](https://elijahchia.gitbook.io/ctf-blog/advent-of-ctf-2024/help-pwn.md): An interesting pwn challenge that gives us really powerful primitives from the get-go
- [Backdoor CTF 24](https://elijahchia.gitbook.io/ctf-blog/backdoor-ctf-24.md)
- [\[rev\] Ratatouille](https://elijahchia.gitbook.io/ctf-blog/backdoor-ctf-24/rev-ratatouille.md): Gameboy binary reversing
- [HKCERT CTF 24](https://elijahchia.gitbook.io/ctf-blog/hkcert-ctf-24.md): This was a 48-hour CTF organised by HKCERT and HKPC. My team G04T3DP30PL3 emerged 37th amongst international teams and 58th amongst all teams.
- [Shellcode Runner 3 + Revenge (pwn)](https://elijahchia.gitbook.io/ctf-blog/hkcert-ctf-24/shellcode-runner-3-+-revenge-pwn.md): Your favorite series of Shellcode runners is back! This time, we're not limiting you with any sandboxes. This should be an easy challenge...right?
- [ISH (1) (pwn)](https://elijahchia.gitbook.io/ctf-blog/hkcert-ctf-24/ish-1-pwn.md): Shell(a.k.a sh) is a text-based interface where users can type commands to interact with the operating system. I'm trying to implement a shell using ISA, I call it ISH.
- [Cyp.ress (rev)](https://elijahchia.gitbook.io/ctf-blog/hkcert-ctf-24/cyp.ress-rev.md): You will get sser.pyc when you reverse the title. Now reverse it back for me.
- [Void (rev)](https://elijahchia.gitbook.io/ctf-blog/hkcert-ctf-24/void-rev.md): I made a simple webpage that checks whether the flag is correct... Wait, where are the flag-checking functions?
- [ECSC 2024](https://elijahchia.gitbook.io/ctf-blog/ecsc-2024.md)
- [OffTopic (crypto)](https://elijahchia.gitbook.io/ctf-blog/ecsc-2024/offtopic-crypto.md): This was the only challenge I solved during the CTF. It had 30 solves in total.
- [Greyhats WelcomeCTF 24](https://elijahchia.gitbook.io/ctf-blog/greyhats-welcomectf-24.md): My team participated in the NUS Greyhats WelcomeCTF 2024 and came in first with a score of 35943. We solved 7/7 misc, 10/10 forensics, 6/9 web, 8/8 reverse, 8/8 crypto and 7/8 pwn challenges.
- [EE2026 (misc)](https://elijahchia.gitbook.io/ctf-blog/greyhats-welcomectf-24/ee2026-misc.md): Hardware challenge requiring vivado and some understanding of circuit schematics.
- [UIUCTF 24](https://elijahchia.gitbook.io/ctf-blog/uiuctf-24.md): Final placing: 54/959 (top 6%) with 5163 points! :D
- [Syscalls (pwn)](https://elijahchia.gitbook.io/ctf-blog/uiuctf-24/syscalls-pwn.md): You can't escape this fortress of security.
- [Summarize (rev)](https://elijahchia.gitbook.io/ctf-blog/uiuctf-24/summarize-rev.md): All you have to do is find six numbers. How hard can that be?
- [X Marked the Spot (crypto)](https://elijahchia.gitbook.io/ctf-blog/uiuctf-24/x-marked-the-spot-crypto.md): A perfect first challenge for beginners. Who said pirates can't ride trains...
- [Without a Trace (crypto)](https://elijahchia.gitbook.io/ctf-blog/uiuctf-24/without-a-trace-crypto.md): Gone with the wind, can you find my flag?
- [Determined (crypto)](https://elijahchia.gitbook.io/ctf-blog/uiuctf-24/determined-crypto.md): "It is my experience that proofs involving matrices can be shortened by 50% if one throws the matrices out."  Emil Artin
- [Naptime (crypto)](https://elijahchia.gitbook.io/ctf-blog/uiuctf-24/naptime-crypto.md): I'm pretty tired. Don't leak my flag while I'm asleep.
- [Snore Signatures (crypto)](https://elijahchia.gitbook.io/ctf-blog/uiuctf-24/snore-signatures-crypto.md): These signatures are a bore!
- [Jelly CTF 24](https://elijahchia.gitbook.io/ctf-blog/jelly-ctf-24.md)
- [Cherry (crypto)](https://elijahchia.gitbook.io/ctf-blog/jelly-ctf-24/cherry-crypto.md): A Starknight hacked an old slot machine and turned it into something strange?! I heard that you win a secret message if you manage to get triple cherries, but...
- [the\_brewing\_secrets (crypto)](https://elijahchia.gitbook.io/ctf-blog/jelly-ctf-24/the_brewing_secrets-crypto.md): Rumour has it Sakana stores the secret recipes for Phase Connect's coffee blends in his 'super secure laboratory'. Can you hack your way in?
- [vsCTF 24](https://elijahchia.gitbook.io/ctf-blog/vsctf-24.md)
- [Dream (crypto)](https://elijahchia.gitbook.io/ctf-blog/vsctf-24/dream-crypto.md): I hear python MT can be broken with 624 outputs, but I only really need 8 random numbers. Surely you can't break it... right?
- [Cosmic Ray V3 (pwn)](https://elijahchia.gitbook.io/ctf-blog/vsctf-24/cosmic-ray-v3-pwn.md): I promise it's the last one. The grand finale to the cosmic trinity. Good luck!
- [AKASEC CTF 24](https://elijahchia.gitbook.io/ctf-blog/akasec-ctf-24.md)
- [Warmup (pwn)](https://elijahchia.gitbook.io/ctf-blog/akasec-ctf-24/warmup-pwn.md): Here's something to get you warmed up, spin that gdb up.
- [Good\_trip (pwn)](https://elijahchia.gitbook.io/ctf-blog/akasec-ctf-24/good_trip-pwn.md): if you think about it? it doesn't make any sense. GOOOOD TRIP
- [Sperm Rev (rev)](https://elijahchia.gitbook.io/ctf-blog/akasec-ctf-24/sperm-rev-rev.md): before baby rev, there was sperm rev <3 solve it fast to win another race in your life.
- [Paranoia (rev)](https://elijahchia.gitbook.io/ctf-blog/akasec-ctf-24/paranoia-rev.md): im baby
- [Grip (rev)](https://elijahchia.gitbook.io/ctf-blog/akasec-ctf-24/grip-rev.md): its...its...Grippy
- [Risks (rev)](https://elijahchia.gitbook.io/ctf-blog/akasec-ctf-24/risks-rev.md): theres this pretty cool isa called riscv it sounds awesome.
- [Lost (crypto)](https://elijahchia.gitbook.io/ctf-blog/akasec-ctf-24/lost-crypto.md): Do you know the feeling of losing a part of you !!
- [L3AK CTF 24](https://elijahchia.gitbook.io/ctf-blog/l3ak-ctf-24.md)
- [oorrww (pwn)](https://elijahchia.gitbook.io/ctf-blog/l3ak-ctf-24/oorrww-pwn.md): I didn't manage to solve this challenge during the CTF, but upsolved it after looking at others' solutions!
- [angry (rev)](https://elijahchia.gitbook.io/ctf-blog/l3ak-ctf-24/angry-rev.md)
- [Related (crypto)](https://elijahchia.gitbook.io/ctf-blog/l3ak-ctf-24/related-crypto.md)
- [BatBot (web-misc)](https://elijahchia.gitbook.io/ctf-blog/l3ak-ctf-24/batbot-web-misc.md)
- [Matrix Magic (crypto)](https://elijahchia.gitbook.io/ctf-blog/l3ak-ctf-24/matrix-magic-crypto.md)
- [CDDC Qualifiers 2024](https://elijahchia.gitbook.io/ctf-blog/cddc-qualifiers-2024.md)
- [WASM (rev)](https://elijahchia.gitbook.io/ctf-blog/cddc-qualifiers-2024/wasm-rev.md)
- [crashMe (pwn)](https://elijahchia.gitbook.io/ctf-blog/cddc-qualifiers-2024/crashme-pwn.md)