security researcher, 🦙@AlpacaHack, ja:@2llr
Joined March 2016
- Tweets 1,342
- Following 563
- Followers 2,210
- Likes 5,773
103 Photos and videos
A new style of CTF for the AI era. Entertainment, not competition...
May 31
🎉今日でDaily AlpacaHackが始まってから半年！
これまで2,572人に遊んでいただき、182問の問題に、44,846個のフラグが提出されました！
これからも、競技の枠を超えた、新しい時代のCTFを目指して運営していきます🦙
12
622
minaminao retweeted
10 Dec 2025
We've launched Daily AlpacaHack, our daily CTF challenge 🎄
Beginner-friendly challenges every day:
• New problems on weekdays
• Selected problems from external CTFs on weekends
Now fully available in English!
alpacahack.com/daily?lang=en
7
59
3,892
I participated in ICC 2025. ICC is a CTF where teams compete by continent, with both Jeopardy-style and Attack & Defense CTFs.
I wanted to share a fun story from the A&D, where I tried exploit other teams internal tools.
Thanks to the organizers and players @icctokyo2025
1
6
71
5,759
I was on the dev team. Thank you for playing and supporting this event!
The award ceremony and the entire event of ICC TOKYO 2025 have concluded.
Thank you for the players' hard-fought match!
We appreciate support and effort of everyone who supported ICC TOKYO 2025.
#icctokyo2025
6
914
ctf-blockchain has hit 1k stars. thanks for all the fun challenges!
github.com/minaminao/ctf-blo…
1
11
1,006
pushed the challs for hitcon, 07ctf, and cbc github.com/minaminao/my-ctf-…
tried making a rev one on EVM that could easily be solved using a symbolic execution engine like hevm, but it ended up with 0 solves😭
hevm is now highly compatible with Foundry, the experience was quite good
1
1
38
3,024
minaminao retweeted
19 Aug 2025
HITCON CTF 2025
Date: UTC 08/22 14:00 ~ 08/24 14:00
ctf2025.hitcon.org
Thanks to @vinami from DeFiHackLabs for creating the web3 challenges for HITCON.
2
11
2,291
minaminao retweeted
1 Aug 2025
🎯 ACSC 2025 Registration is OPEN!
🕛 Start: Aug 16 (Sat) 12:00 noon
🕛 End: Aug 17 (Sun) 12:00 noon
🔗 Register now: docs.google.com/forms/d/e/1F…
🌐 Official site: acsc.asia/
🎮 The game is open to ALL players.
🌍 Finalists will be selected from ACSC member countries for #ICCTokyo2025 — but everyone’s welcome to join and play!
#ctf #acsc_ctf #icctokyo2025 #cybersecurity
2
31
63
35,685
Long time no post — I've been casually running a CTF platform for individual players called @AlpacaHack for the past year. This weekend, we're hosting a new 6-hour Crypto round. Feel free to give it a try!
alpacahack.com/ctfs/round-13
1
13
1,141
minaminao retweeted
26 Jan 2025
Finally completed the writeup for my challenge (ffmac) in AlpacaHack Round 9 (Crypto)
github.com/maple3142/My-CTF-…
1
4
23
3,592
you can try it using github.com/paradigmxyz/forge…
6
1,050
I created a challenge at SECCON CTF that explored EVM Object Format (EOF)🧩
It revealed two emerging pitfalls: Contract Recreation Failures and Call Return Mishandling.
It was tough—only 2 teams solved. Give it a try to deepen your understanding of EOF:
github.com/minaminao/my-ctf-…
3
8
84
9,220
Writeup: github.com/minaminao/my-ctf-…
Congratulations and thank you to @tonyke_bot and @publicqi's team, and @dicegangctf, for solving this challenge!
1
7
985
I'm contributing challenges for SECCON CTF again this year :)
Date: Nov 23, 05:00 UTC – for 24 hours
ctftime.org/event/2478/ @secconctf
2
42
2,334
loving this beginner-friendly CTF, going on-site for the in-person challenges tomorrow
12 Nov 2024
competition is heating up for the top of the CTF at @EFDevcon 🔥
can you beat them?
ctf.therektgames.com/
13
1,473
