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chocorusk

@nuo_chocorusk

AUTHORED CHALLENGES

OPEN DATECHALLENGESOLVES

2026/02/20

Stealerusk
Rev
40 solves

2026/02/04

HellCouple
Crypto
66 solves

2026/01/26

ToyPQC
Crypto
102 solves

2026/01/18

ChaChaCha
Crypto
152 solves

2025/12/11

Sugoi Flag Checker
Rev
193 solves

2025/01/26

RSAMPC
Crypto
35 solves

2025/01/26

Equivalent Privacy Wired
Crypto
9 solves

2025/01/26

addprimes
Crypto
27 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
Writeup for Bashrunner
ja
Bashrunner

last month

Author's Writeup for ChaChaCha
ja
official
ChaChaCha

last month

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

2 months ago

Writeup for SECCON CTF 13 Quals
ja
reiwa_rot13

last year

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

last year

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

guess.js
Misc
Daily AlpacaHack

86 solves

5 hours ago

Another Login Challenge
Web
Daily AlpacaHack

80 solves

21 hours ago

iwashi
Crypto
Daily AlpacaHack B-SIDE

32 solves

yesterday

nc magic
Misc
Daily AlpacaHack

126 solves

yesterday

kappa overflow
Pwn
Daily AlpacaHack

95 solves

yesterday

high and low
Crypto
Daily AlpacaHack

75 solves

2 days ago

Find XOR key
Crypto
Daily AlpacaHack

98 solves

2 days ago

💯
Misc
Daily AlpacaHack

93 solves

3 days ago

FLAG OVER
Misc
Daily AlpacaHack

97 solves

4 days ago

misdirection
Rev
Daily AlpacaHack

146 solves

last week

destructuring
Misc
Daily AlpacaHack

134 solves

last week

magic number
Misc
Daily AlpacaHack

99 solves

last week

Alert my Flag
Web
Daily AlpacaHack

124 solves

last week

Flag Printer 2026
Misc
Daily AlpacaHack

148 solves

last week

glibc's secret function
Rev
Daily AlpacaHack

146 solves

last week

Bars
Web
Daily AlpacaHack

197 solves

last week

One Byte Padding Oracle Attack
Crypto
Daily AlpacaHack

68 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

Noob programmer
Pwn
Daily AlpacaHack

93 solves

2 weeks ago

Alpaillier
Crypto
Daily AlpacaHack

111 solves

2 weeks ago

Alpaca Quest
Rev
Daily AlpacaHack

105 solves

2 weeks ago

CopperCopperCopper
Crypto
Daily AlpacaHack

86 solves

3 weeks ago

ECRSA
Crypto
Daily AlpacaHack B-SIDE

45 solves

3 weeks ago

Dancing Cursor
RevMisc
Daily AlpacaHack

101 solves

3 weeks ago

wages of sin()
RevMisc
Daily AlpacaHack

86 solves

3 weeks ago

The World
Misc
Daily AlpacaHack

174 solves

last month

RRe_Time_Limiter
Crypto
Daily AlpacaHack

164 solves

last month

Magic Engine
Web
Daily AlpacaHack

241 solves

last month

read-a-binary
Rev
Daily AlpacaHack

202 solves

last month

Inu Profile
Web
Daily AlpacaHack B-SIDE

87 solves

last month

Substance
Crypto
Daily AlpacaHack

224 solves

last month

Stateless Auth
Web
Daily AlpacaHack

160 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

147 solves

last month

Short Writer
Pwn
Daily AlpacaHack

116 solves

last month

Five Alpacas
Crypto
Daily AlpacaHack

183 solves

last month

free-comment
Misc
Daily AlpacaHack

145 solves

last month

I wanna be the Admin
Web
Daily AlpacaHack

255 solves

2 months ago

Basic Buffer Overflow
Pwn
Daily AlpacaHack

170 solves

2 months ago

crazython
Rev
Daily AlpacaHack

172 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
MiscCrypto
Daily AlpacaHack

287 solves

2 months ago

Fushigi Crawler
Web
Daily AlpacaHack

310 solves

2 months ago

Ruby Flag Checker
Rev
Daily AlpacaHack

266 solves

2 months ago

super-tomato
Crypto
Daily AlpacaHack

352 solves

2 months ago

RBG
Crypto
Daily AlpacaHack

119 solves

2 months ago

108
Misc
Daily AlpacaHack

269 solves

2 months ago

one-p-rsa
Crypto
Daily AlpacaHack

211 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

152 solves

2 months ago

Xmas Login
Web
Daily AlpacaHack

313 solves

2 months ago

cat3
Misc
Daily AlpacaHack

207 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

231 solves

2 months ago

alloc-101
Pwn
Daily AlpacaHack

205 solves

2 months ago

Twilight
Rev
Daily AlpacaHack

216 solves

2 months ago

login-bonus
Pwn
Daily AlpacaHack

236 solves

2 months ago

🐈
Web
Daily AlpacaHack

288 solves

2 months ago

Flag Printer 2100
Rev
Daily AlpacaHack

230 solves

2 months ago

power_obfus_royalty
Rev
Daily AlpacaHack

194 solves

2 months ago

Safe Prime
Crypto
Daily AlpacaHack

240 solves

3 months ago

Sugoi Flag Checker
Rev
Daily AlpacaHack

193 solves

3 months ago

Alpaca Bank
Web
Daily AlpacaHack

305 solves

3 months ago

Read Assembly
Rev
Daily AlpacaHack

295 solves

3 months ago

hit-and-miss
Misc
Daily AlpacaHack

358 solves

3 months ago

Fully Padded RSA
Crypto
Daily AlpacaHack

224 solves

3 months ago

Integer Writer
Pwn
Daily AlpacaHack

298 solves

3 months ago

size limit
Crypto
Daily AlpacaHack

290 solves

3 months ago

Leaked Flag Checker
Rev
Daily AlpacaHack

513 solves

3 months ago

a fact of CTF
Crypto
Daily AlpacaHack

781 solves

3 months ago

Emojify
Web
Daily AlpacaHack

532 solves

3 months ago

AlpacaHack 2100
Misc
Daily AlpacaHack

1377 solves

3 months ago

simpleoverflow
Pwn
Daily AlpacaHack

459 solves

3 months ago

MissingNo.2
Crypto
AlpacaHack Round 13 (Crypto)

8 solves

7 months ago

MissingNo.1
Crypto
AlpacaHack Round 13 (Crypto)

11 solves

7 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

Zero-sum game
Crypto
AlpacaHack Round 12 (Crypto)

4 solves

8 months ago

Flag Sharing
Crypto
AlpacaHack Round 12 (Crypto)

10 solves

8 months ago

OTEC
Crypto
AlpacaHack Round 12 (Crypto)

39 solves

8 months ago

RSARSARSARSARSARSA
Crypto
AlpacaHack Round 12 (Crypto)

79 solves

8 months ago

Trillion Ether
Blockchain
SECCON CTF 13 Quals

7 solves

last year

Tidal wave
Crypto
SECCON CTF 13 Quals

5 solves

last year

dual_summon
Crypto
SECCON CTF 13 Quals

9 solves

last year

reiwa_rot13
Crypto
SECCON CTF 13 Quals

29 solves

last year

addprimes
Crypto
AlpacaHack Round 9 (Crypto)

27 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

ffmac
Crypto
AlpacaHack Round 9 (Crypto)

8 solves

last year

Alpaca Poll
Web
AlpacaHack Round 7 (Web)

128 solves

last year

Treasure Hunt
Web
AlpacaHack Round 7 (Web)

266 solves

last year

SchnorrLCG
Crypto
AlpacaHack Round 5 (Crypto)

22 solves

last year

NNNN
Crypto
AlpacaHack Round 5 (Crypto)

48 solves

last year

XorshiftStream
Crypto
AlpacaHack Round 5 (Crypto)

63 solves

last year

Broadcasting NTRU
Crypto
AlpacaHack Round 5 (Crypto)

10 solves

last year

Simple Flag Checker
Rev
AlpacaHack Round 4 (Rev)

125 solves

last year

Hat Trick
Crypto
AlpacaHack Round 3 (Crypto)

66 solves

last year

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

74 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

echo
Pwn
AlpacaHack Round 1 (Pwn)

347 solves

last year

Pico Note 1
Web
AlpacaHack Round 2 (Web)

80 solves

last year

CaaS
Web
AlpacaHack Round 2 (Web)

92 solves

last year

Simple Login
Web
AlpacaHack Round 2 (Web)

591 solves

last year

Welcome
Misc

1476 solves

last year