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@chocorusk

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chocorusk

@nuo_chocorusk

AUTHORED CHALLENGES

OPEN DATECHALLENGESOLVES

2026/01/18

ChaChaCha
Crypto
128 solves

2025/12/11

Sugoi Flag Checker
Rev
178 solves

2025/01/26

RSAMPC
Crypto
33 solves

2025/01/26

Equivalent Privacy Wired
Crypto
8 solves

2025/01/26

addprimes
Crypto
25 solves

2024/10/12

Broadcasting NTRU
Crypto
10 solves

CTF HISTORY

START DATECTFRANK

2025/07/20

AlpacaHack Round 13 (Crypto)
1 / 62

2025/07/06

AlpacaHack Round 12 (Crypto)
2 / 78

2025/01/26

AlpacaHack Round 9 (Crypto)
20 / 138

2024/11/30

AlpacaHack Round 7 (Web)
22 / 458

2024/11/03

AlpacaHack Round 6 (Pwn)
58 / 197

2024/10/12

AlpacaHack Round 5 (Crypto)
32 / 247

2024/10/05

AlpacaHack Round 4 (Rev)
38 / 279

2024/09/15

AlpacaHack Round 3 (Crypto)
3 / 239

2024/09/01

AlpacaHack Round 2 (Web)
58 / 300

WRITEUPS

WRITEUPCREATED AT
Author's Writeup for ChaChaCha
ja
official
ChaChaCha

3 days ago

Author’s Writeup for Sugoi Flag Checker
ja
official
Sugoi Flag Checker

last month

Writeup for SECCON CTF 13 Quals
ja
reiwa_rot13

11 months ago

AlpacaHack Round 9 (Crypto) 作問者writeup
ja
official
AlpacaHack Round 9 (Crypto)

12 months ago

Broadcasting NTRU 作問者writeup
ja
official
Broadcasting NTRU

last year

Writeup for AlpacaHack Round 3 (Crypto)
ja
AlpacaHack Round 3 (Crypto)

last year

SOLVED CHALLENGES

CHALLENGESOLVES

SOLVED AT

Animal Viewer
Web
Daily AlpacaHack

105 solves

yesterday

dockerstack
Misc
Daily AlpacaHack

133 solves

2 days ago

system-v
Rev
Daily AlpacaHack

95 solves

3 days ago

ChaChaCha
Crypto
Daily AlpacaHack

128 solves

3 days ago

dice roll
Web
Daily AlpacaHack

148 solves

5 days ago

Base Length
Misc
Daily AlpacaHack

127 solves

6 days ago

Short Writer
Pwn
Daily AlpacaHack

95 solves

last week

Five Alpacas
Crypto
Daily AlpacaHack

148 solves

last week

free-comment
Misc
Daily AlpacaHack

133 solves

last week

I wanna be the Admin
Web
Daily AlpacaHack

188 solves

last week

Basic Buffer Overflow
Pwn
Daily AlpacaHack

143 solves

last week

crazython
Rev
Daily AlpacaHack

155 solves

last week

RSA2026
Crypto
Daily AlpacaHack

172 solves

last week

SwapSwap
Misc
Daily AlpacaHack

215 solves

2 weeks ago

secret-table
Web
Daily AlpacaHack

204 solves

2 weeks ago

Square RSA
Crypto
Daily AlpacaHack

186 solves

2 weeks ago

jailiaj
Misc
Daily AlpacaHack

209 solves

2 weeks ago

Encoding Basics
MiscCrypto
Daily AlpacaHack

225 solves

2 weeks ago

Fushigi Crawler
Web
Daily AlpacaHack

241 solves

2 weeks ago

Ruby Flag Checker
Rev
Daily AlpacaHack

212 solves

2 weeks ago

super-tomato
Crypto
Daily AlpacaHack

274 solves

3 weeks ago

RBG
Crypto
Daily AlpacaHack

112 solves

3 weeks ago

108
Misc
Daily AlpacaHack

219 solves

3 weeks ago

one-p-rsa
Crypto
Daily AlpacaHack

180 solves

3 weeks ago

cha-ll-enge
Rev
Daily AlpacaHack

132 solves

3 weeks ago

simpleoverwrite
Pwn
Daily AlpacaHack

159 solves

3 weeks ago

Useful Machine
Rev
Daily AlpacaHack

142 solves

4 weeks ago

Xmas Login
Web
Daily AlpacaHack

247 solves

4 weeks ago

cat3
Misc
Daily AlpacaHack

187 solves

4 weeks ago

Rotten Beef
Pwn
Daily AlpacaHack

171 solves

last month

Log Viewer
Web
Daily AlpacaHack

192 solves

last month

RSA debug?
Crypto
Daily AlpacaHack

168 solves

last month

omikuji
Web
Daily AlpacaHack

202 solves

last month

alloc-101
Pwn
Daily AlpacaHack

192 solves

last month

Twilight
Rev
Daily AlpacaHack

193 solves

last month

login-bonus
Pwn
Daily AlpacaHack

215 solves

last month

🐈
Web
Daily AlpacaHack

249 solves

last month

Flag Printer 2100
Rev
Daily AlpacaHack

203 solves

last month

power_obfus_royalty
Rev
Daily AlpacaHack

179 solves

last month

Safe Prime
Crypto
Daily AlpacaHack

223 solves

last month

Sugoi Flag Checker
Rev
Daily AlpacaHack

178 solves

last month

Alpaca Bank
Web
Daily AlpacaHack

264 solves

last month

Read Assembly
Rev
Daily AlpacaHack

256 solves

last month

hit-and-miss
Misc
Daily AlpacaHack

287 solves

last month

Fully Padded RSA
Crypto
Daily AlpacaHack

205 solves

last month

Integer Writer
Pwn
Daily AlpacaHack

264 solves

last month

size limit
Crypto
Daily AlpacaHack

256 solves

last month

Leaked Flag Checker
Rev
Daily AlpacaHack

419 solves

last month

a fact of CTF
Crypto
Daily AlpacaHack

640 solves

last month

Emojify
Web
Daily AlpacaHack

450 solves

last month

AlpacaHack 2100
Misc
Daily AlpacaHack

1036 solves

last month

simpleoverflow
Pwn
Daily AlpacaHack

381 solves

last month

MissingNo.2
Crypto
AlpacaHack Round 13 (Crypto)

6 solves

6 months ago

MissingNo.1
Crypto
AlpacaHack Round 13 (Crypto)

9 solves

6 months ago

Polynomial Puzzle
Crypto
AlpacaHack Round 13 (Crypto)

4 solves

6 months ago

Jerr0-day
Crypto
AlpacaHack Round 13 (Crypto)

11 solves

6 months ago

Jerry's flag checker
Crypto
AlpacaHack Round 13 (Crypto)

29 solves

6 months ago

Zero-sum game
Crypto
AlpacaHack Round 12 (Crypto)

3 solves

6 months ago

Flag Sharing
Crypto
AlpacaHack Round 12 (Crypto)

9 solves

6 months ago

OTEC
Crypto
AlpacaHack Round 12 (Crypto)

38 solves

6 months ago

RSARSARSARSARSARSA
Crypto
AlpacaHack Round 12 (Crypto)

78 solves

6 months ago

Trillion Ether
Blockchain
SECCON CTF 13 Quals

5 solves

11 months ago

Tidal wave
Crypto
SECCON CTF 13 Quals

3 solves

11 months ago

dual_summon
Crypto
SECCON CTF 13 Quals

7 solves

11 months ago

reiwa_rot13
Crypto
SECCON CTF 13 Quals

24 solves

11 months ago

addprimes
Crypto
AlpacaHack Round 9 (Crypto)

25 solves

12 months ago

Equivalent Privacy Wired
Crypto
AlpacaHack Round 9 (Crypto)

8 solves

12 months ago

RSAMPC
Crypto
AlpacaHack Round 9 (Crypto)

33 solves

12 months ago

ffmac
Crypto
AlpacaHack Round 9 (Crypto)

8 solves

12 months ago

Alpaca Poll
Web
AlpacaHack Round 7 (Web)

125 solves

last year

Treasure Hunt
Web
AlpacaHack Round 7 (Web)

261 solves

last year

SchnorrLCG
Crypto
AlpacaHack Round 5 (Crypto)

22 solves

last year

NNNN
Crypto
AlpacaHack Round 5 (Crypto)

45 solves

last year

XorshiftStream
Crypto
AlpacaHack Round 5 (Crypto)

60 solves

last year

Broadcasting NTRU
Crypto
AlpacaHack Round 5 (Crypto)

10 solves

last year

Simple Flag Checker
Rev
AlpacaHack Round 4 (Rev)

124 solves

last year

Hat Trick
Crypto
AlpacaHack Round 3 (Crypto)

64 solves

last year

A Dance of Add and Mul
Crypto
AlpacaHack Round 3 (Crypto)

72 solves

last year

Rainbow Sweet Alchemist
Crypto
AlpacaHack Round 3 (Crypto)

121 solves

last year

qrime
Crypto
AlpacaHack Round 3 (Crypto)

245 solves

last year

echo
Pwn
AlpacaHack Round 1 (Pwn)

330 solves

last year

Pico Note 1
Web
AlpacaHack Round 2 (Web)

75 solves

last year

CaaS
Web
AlpacaHack Round 2 (Web)

90 solves

last year

Simple Login
Web
AlpacaHack Round 2 (Web)

548 solves

last year

Welcome
Misc

1369 solves

last year