@yu212 - AlpacaHack

yu212

@Yu_212_MC

AUTHORED CHALLENGES

OPEN DATE	CHALLENGE	SOLVES
2026/03/14	BINARY IN THE FUTURE. Rev	66 solves
2026/03/14	Red and Black Rev	3 solves
2026/03/14	javajail Misc	55 solves
2026/03/14	Yajirin Rev Misc	0 solves
2026/03/14	Faulty AES Crypto	62 solves
2026/03/14	Double Hint RSA Crypto	29 solves
2026/03/14	Expensive Operator Crypto	1 solve
2026/03/14	El Dorado Crypto	1 solve
2026/03/14	Dream of You Web	27 solves
2026/03/14	Fault Tolerance Py Misc	8 solves
2026/03/14	verified-msg Pwn Crypto	6 solves
2026/03/14	Single Hint RSA Crypto	113 solves
2026/03/14	Yet Another Injection Challenge Misc	27 solves
2026/03/14	RANDOM IN THE FUTURE. Crypto	26 solves
2026/03/14	Faulty SHA Crypto	1 solve
2026/01/29	Linear Coffee Generator Crypto	109 solves
2026/01/23	Paca Paca Authenticator Crypto	120 solves
2025/12/16	doloR Sit Amet Crypto	2 solves
2025/12/16	Noisy Channel Crypto	1 solve
2025/12/16	doloR Sit Amet Revenge Crypto	2 solves
2025/12/07	Fully Padded RSA Crypto	224 solves
2025/07/06	RSARSARSARSARSARSA Crypto	79 solves
2025/07/06	Flag Sharing Crypto	10 solves
2025/07/06	OTEC Crypto	39 solves
2025/07/06	Zero-sum game Crypto	4 solves

CTF HISTORY

START DATE	CTF	RANK
2025/07/20	AlpacaHack Round 13 (Crypto)	8 / 62
2025/05/17	AlpacaHack Round 11 (Web)	13 / 213
2025/03/23	AlpacaHack Round 10 (Pwn)	43 / 95
2025/03/01	SECCON CTF 13 決勝観戦CTF	101 / 233
2025/01/26	AlpacaHack Round 9 (Crypto)	20 / 138
2024/12/30	AlpacaHack Round 8 (Rev)	5 / 316
2024/11/30	AlpacaHack Round 7 (Web)	79 / 458
2024/11/03	AlpacaHack Round 6 (Pwn)	46 / 197
2024/10/12	AlpacaHack Round 5 (Crypto)	8 / 247
2024/09/15	AlpacaHack Round 3 (Crypto)	6 / 239
2024/09/01	AlpacaHack Round 2 (Web)	18 / 300
2024/08/18	AlpacaHack Round 1 (Pwn)	33 / 174

WRITEUPS

WRITEUP	CREATED AT
Writeup for HellCouple ja HellCouple	last month
Author's Writeup for Linear Coffee Generator ja official Linear Coffee Generator	last month
Author's Writeup for Paca Paca Authenticator ja official Paca Paca Authenticator	last month
Writeup for Fully Padded RSA ja official Fully Padded RSA	3 months ago
AlpacaHack Round 12 (Crypto) 作問者writeup ja official Flag Sharing	8 months ago
Writeup for AlpacaHack Round 3 (Crypto) ja AlpacaHack Round 3 (Crypto)	last year
frozen cake 初心者向け解説 ja frozen cake	last year

SOLVED CHALLENGES

CHALLENGE	SOLVES	SOLVED AT
flag.txt Misc Daily AlpacaHack	83 solves	yesterday
Heuristic IPPON Misc Daily AlpacaHack	126 solves	2 days ago
kappa overflow Pwn Daily AlpacaHack	101 solves	4 days ago
Find XOR key Crypto Daily AlpacaHack	100 solves	5 days ago
💯 Misc Daily AlpacaHack	100 solves	6 days ago
FLAG OVER Misc Daily AlpacaHack	102 solves	last week
reiwa_rot13 Crypto SECCON CTF 13 Quals	29 solves	last week
guess.js Misc Daily AlpacaHack	88 solves	last week
high and low Crypto Daily AlpacaHack	78 solves	last week
magic number Misc Daily AlpacaHack	102 solves	last week
Alert my Flag Web Daily AlpacaHack	128 solves	last week
9️⃣ Misc Daily AlpacaHack B-SIDE	43 solves	last week
Flag Printer 2026 Misc Daily AlpacaHack	152 solves	last week
glibc's secret function Rev Daily AlpacaHack	152 solves	last week
Bars Web Daily AlpacaHack	205 solves	2 weeks ago
pyjs Misc Daily AlpacaHack	77 solves	2 weeks ago
Rock Paper Scissors Lizard Spock Web Daily AlpacaHack	87 solves	2 weeks ago
One Byte Padding Oracle Attack Crypto Daily AlpacaHack	69 solves	2 weeks ago
useful-gadget Pwn Daily AlpacaHack B-SIDE	43 solves	2 weeks ago
Alpaca Rangers Web Daily AlpacaHack	132 solves	2 weeks ago
hit-and-hit Misc Daily AlpacaHack	80 solves	2 weeks ago
Alpaca Quest Rev Daily AlpacaHack	105 solves	3 weeks ago
Noob programmer Pwn Daily AlpacaHack	93 solves	3 weeks ago
Stealerusk Rev Daily AlpacaHack B-SIDE	40 solves	3 weeks ago
CopperCopperCopper Crypto Daily AlpacaHack	86 solves	3 weeks ago
Dancing Cursor Rev Misc Daily AlpacaHack	101 solves	3 weeks ago
Pickle Loader Misc Daily AlpacaHack	111 solves	3 weeks ago
Disappeared Pwn Daily AlpacaHack	105 solves	3 weeks ago
ECRSA Crypto Daily AlpacaHack B-SIDE	45 solves	3 weeks ago
wages of sin() Rev Misc Daily AlpacaHack	86 solves	3 weeks ago
Alpaillier Crypto Daily AlpacaHack	112 solves	4 weeks ago
ret2basics Pwn Daily AlpacaHack B-SIDE	39 solves	4 weeks ago
You are being redirected Web Daily AlpacaHack	109 solves	4 weeks ago
simple ROP Pwn Daily AlpacaHack	101 solves	4 weeks ago
nc magic Misc Daily AlpacaHack	127 solves	last month
AAAAAAAAEEEEEEEESSSSSSSS Crypto Daily AlpacaHack	113 solves	last month
invisible-grep Misc Daily AlpacaHack B-SIDE	37 solves	last month
destructuring Misc Daily AlpacaHack	134 solves	last month
Alpaca-Llama Ranch Pwn Daily AlpacaHack	114 solves	last month
Plz Login Web Daily AlpacaHack	206 solves	last month
Compressor Misc Daily AlpacaHack	102 solves	last month
misdirection Rev Daily AlpacaHack	147 solves	last month
The World Misc Daily AlpacaHack	175 solves	last month
HellCouple Crypto Daily AlpacaHack B-SIDE	66 solves	last month
RRe_Time_Limiter Crypto Daily AlpacaHack	166 solves	last month
Magic Engine Web Daily AlpacaHack	243 solves	last month
read-a-binary Rev Daily AlpacaHack	208 solves	last month
Substance Crypto Daily AlpacaHack	228 solves	last month
Inu Profile Web Daily AlpacaHack B-SIDE	87 solves	last month
optimal-sort Misc Daily AlpacaHack	97 solves	last month
Linear Coffee Generator Crypto Daily AlpacaHack	109 solves	last month
shellcode-101 Pwn Daily AlpacaHack	123 solves	last month
No JS Web Daily AlpacaHack	126 solves	last month
ToyPQC Crypto Daily AlpacaHack	103 solves	last month
git gc Misc Daily AlpacaHack	144 solves	last month
Stateless Auth Web Daily AlpacaHack	161 solves	last month
Paca Paca Authenticator Crypto Daily AlpacaHack	120 solves	last month
Bashrunner Misc Daily AlpacaHack	116 solves	last month
Animal Viewer Web Daily AlpacaHack	148 solves	last month
dockerstack Misc Daily AlpacaHack	172 solves	last month
system-v Rev Daily AlpacaHack	115 solves	last month
ChaChaCha Crypto Daily AlpacaHack	152 solves	last month
dice roll Web Daily AlpacaHack	191 solves	last month
Base Length Misc Daily AlpacaHack	148 solves	last month
Short Writer Pwn Daily AlpacaHack	116 solves	last month
Five Alpacas Crypto Daily AlpacaHack	184 solves	2 months ago
free-comment Misc Daily AlpacaHack	145 solves	2 months ago
I wanna be the Admin Web Daily AlpacaHack	257 solves	2 months ago
Basic Buffer Overflow Pwn Daily AlpacaHack	170 solves	2 months ago
crazython Rev Daily AlpacaHack	173 solves	2 months ago
RSA2026 Crypto Daily AlpacaHack	196 solves	2 months ago
SwapSwap Misc Daily AlpacaHack	259 solves	2 months ago
secret-table Web Daily AlpacaHack	249 solves	2 months ago
Square RSA Crypto Daily AlpacaHack	218 solves	2 months ago
jailiaj Misc Daily AlpacaHack	260 solves	2 months ago
Encoding Basics Misc Crypto Daily AlpacaHack	289 solves	2 months ago
Fushigi Crawler Web Daily AlpacaHack	312 solves	2 months ago
Ruby Flag Checker Rev Daily AlpacaHack	267 solves	2 months ago
super-tomato Crypto Daily AlpacaHack	352 solves	2 months ago
108 Misc Daily AlpacaHack	272 solves	2 months ago
RBG Crypto Daily AlpacaHack	120 solves	2 months ago
one-p-rsa Crypto Daily AlpacaHack	213 solves	2 months ago
cha-ll-enge Rev Daily AlpacaHack	147 solves	2 months ago
simpleoverwrite Pwn Daily AlpacaHack	181 solves	2 months ago
Useful Machine Rev Daily AlpacaHack	153 solves	2 months ago
Xmas Login Web Daily AlpacaHack	315 solves	2 months ago
cat3 Misc Daily AlpacaHack	208 solves	2 months ago
Rotten Beef Pwn Daily AlpacaHack	191 solves	2 months ago
Log Viewer Web Daily AlpacaHack	214 solves	2 months ago
RSA debug? Crypto Daily AlpacaHack	180 solves	2 months ago
omikuji Web Daily AlpacaHack	232 solves	2 months ago
alloc-101 Pwn Daily AlpacaHack	207 solves	2 months ago
Twilight Rev Daily AlpacaHack	218 solves	2 months ago
login-bonus Pwn Daily AlpacaHack	236 solves	2 months ago
🐈 Web Daily AlpacaHack	289 solves	2 months ago
Flag Printer 2100 Rev Daily AlpacaHack	232 solves	3 months ago
power_obfus_royalty Rev Daily AlpacaHack	195 solves	3 months ago
Safe Prime Crypto Daily AlpacaHack	240 solves	3 months ago
Sugoi Flag Checker Rev Daily AlpacaHack	195 solves	3 months ago
Alpaca Bank Web Daily AlpacaHack	306 solves	3 months ago
Read Assembly Rev Daily AlpacaHack	298 solves	3 months ago
hit-and-miss Misc Daily AlpacaHack	359 solves	3 months ago
Fully Padded RSA Crypto Daily AlpacaHack	224 solves	3 months ago
size limit Crypto Daily AlpacaHack	292 solves	3 months ago
simpleoverflow Pwn Daily AlpacaHack	461 solves	3 months ago
Integer Writer Pwn Daily AlpacaHack	301 solves	3 months ago
Leaked Flag Checker Rev Daily AlpacaHack	517 solves	3 months ago
Emojify Web Daily AlpacaHack	536 solves	3 months ago
a fact of CTF Crypto Daily AlpacaHack	791 solves	3 months ago
AlpacaHack 2100 Misc Daily AlpacaHack	1404 solves	3 months ago
Polynomial Puzzle Crypto AlpacaHack Round 13 (Crypto)	5 solves	7 months ago
Jerr0-day Crypto AlpacaHack Round 13 (Crypto)	14 solves	7 months ago
Jerry's flag checker Crypto AlpacaHack Round 13 (Crypto)	32 solves	7 months ago
Redirector Web AlpacaHack Round 11 (Web)	30 solves	10 months ago
Jackpot Web AlpacaHack Round 11 (Web)	159 solves	10 months ago
Kangaroo Pwn AlpacaHack Round 10 (Pwn)	66 solves	11 months ago
ffmac Crypto AlpacaHack Round 9 (Crypto)	8 solves	last year
Equivalent Privacy Wired Crypto AlpacaHack Round 9 (Crypto)	9 solves	last year
RSAMPC Crypto AlpacaHack Round 9 (Crypto)	35 solves	last year
addprimes Crypto AlpacaHack Round 9 (Crypto)	27 solves	last year
subway Rev AlpacaHack Round 8 (Rev)	16 solves	last year
vcipher Rev AlpacaHack Round 8 (Rev)	29 solves	last year
hidden Rev AlpacaHack Round 8 (Rev)	71 solves	last year
masking tape Rev AlpacaHack Round 8 (Rev)	173 solves	last year
Alpaca Poll Web AlpacaHack Round 7 (Web)	129 solves	last year
Treasure Hunt Web AlpacaHack Round 7 (Web)	266 solves	last year
catcpy Pwn AlpacaHack Round 6 (Pwn)	144 solves	last year
inbound Pwn AlpacaHack Round 6 (Pwn)	204 solves	last year
GitFile Explorer Web zer0pts CTF 2022	47 solves	last year
Modern Rome Pwn zer0pts CTF 2022	24 solves	last year
Anti-Fermat Crypto zer0pts CTF 2022	30 solves	last year
NNNN Crypto AlpacaHack Round 5 (Crypto)	48 solves	last year
SchnorrLCG Crypto AlpacaHack Round 5 (Crypto)	22 solves	last year
XorshiftStream Crypto AlpacaHack Round 5 (Crypto)	63 solves	last year
Everything Silver Rev AlpacaHack Round 4 (Rev)	26 solves	last year
pytecode Rev AlpacaHack Round 4 (Rev)	26 solves	last year
Simple Flag Checker Rev AlpacaHack Round 4 (Rev)	125 solves	last year
A Dance of Add and Mul Crypto AlpacaHack Round 3 (Crypto)	74 solves	last year
Hat Trick Crypto AlpacaHack Round 3 (Crypto)	66 solves	last year
Rainbow Sweet Alchemist Crypto AlpacaHack Round 3 (Crypto)	124 solves	last year
qrime Crypto AlpacaHack Round 3 (Crypto)	250 solves	last year
ding-dong-ting-ping Crypto CakeCTF 2023	9 solves	last year
janken vs yoshiking 2 Crypto CakeCTF 2023	16 solves	last year
brand new crypto Crypto CakeCTF 2022	24 solves	last year
luau Rev CakeCTF 2022	34 solves	last year
CakeGEAR Web CakeCTF 2022	79 solves	last year
CaaS Web AlpacaHack Round 2 (Web)	92 solves	last year
Pico Note 1 Web AlpacaHack Round 2 (Web)	80 solves	last year
Simple Login Web AlpacaHack Round 2 (Web)	592 solves	last year
hexecho Pwn AlpacaHack Round 1 (Pwn)	112 solves	last year
echo Pwn AlpacaHack Round 1 (Pwn)	347 solves	last year
Cake Puzzle Rev CakeCTF 2023	20 solves	last year
mimikyu Rev zer0pts CTF 2023	15 solves	last year
read-write Pwn RTACTF 2023 Spring	41 solves	last year
1R-AES Crypto RTACTF 2023 Spring	17 solves	last year
Collision-DES Crypto RTACTF 2023 Spring	37 solves	last year
write Pwn RTACTF 2023 Spring	85 solves	last year
before-write Pwn RTACTF 2023 Spring	160 solves	last year
Reused-AES Crypto RTACTF 2023 Spring	33 solves	last year
XOR-CBC Crypto RTACTF 2023 Spring	77 solves	last year
Welcome Misc	1491 solves	last year
SquareRNG Crypto zer0pts CTF 2023	15 solves	last year
easy_factoring Crypto zer0pts CTF 2023	29 solves	last year
TOWFL Web Cheat CakeCTF 2023	50 solves	last year
decompile me Rev zer0pts CTF 2023	48 solves	last year
vtable4b Pwn CakeCTF 2023	61 solves	last year
nimrev Rev CakeCTF 2022	79 solves	last year
bofww Pwn CakeCTF 2023	38 solves	last year
frozen cake Crypto CakeCTF 2022	70 solves	last year
simple signature Crypto CakeCTF 2023	28 solves	last year
Country DB Web CakeCTF 2023	220 solves	last year

Only archived challenges are displayed here.