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chocorusk

@nuo_chocorusk

AUTHORED CHALLENGES

OPEN DATECHALLENGESOLVES

2026/03/20

Alpacker
Rev
78 solves

2026/02/20

Stealerusk
Rev
45 solves

2026/02/04

HellCouple
Crypto
70 solves

2026/01/26

ToyPQC
Crypto
108 solves

2026/01/18

ChaChaCha
Crypto
157 solves

2025/12/11

Sugoi Flag Checker
Rev
204 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
11 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

2 months ago

Author's Writeup for ChaChaCha
ja
official
ChaChaCha

2 months ago

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

3 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

Panic
Web
Daily AlpacaHack

119 solves

3 days ago

ret2basics
Pwn
Daily AlpacaHack B-SIDE

44 solves

4 days ago

1️⃣
Misc
Daily AlpacaHack

149 solves

4 days ago

Perljail
Misc
Daily AlpacaHack B-SIDE

29 solves

5 days ago

No Content
Web
Daily AlpacaHack

147 solves

5 days ago

fsb-202
Pwn
Daily AlpacaHack B-SIDE

40 solves

6 days ago

login-bonus-2
Pwn
Daily AlpacaHack

82 solves

6 days ago

The Horn
Crypto
Daily AlpacaHack

97 solves

last week

useful-gadget
Pwn
Daily AlpacaHack B-SIDE

46 solves

last week

Impossible Puzzle
Web
Daily AlpacaHack

178 solves

last week

You are my friend
Crypto
Daily AlpacaHack

154 solves

last week

Stealerusk
Rev
Daily AlpacaHack B-SIDE

45 solves

last week

HellCouple
Crypto
Daily AlpacaHack B-SIDE

70 solves

last week

pyjs
Misc
Daily AlpacaHack

82 solves

last week

You are being redirected
Web
Daily AlpacaHack

113 solves

last week

No JS
Web
Daily AlpacaHack

132 solves

last week

Rock Paper Scissors Lizard Spock
Web
Daily AlpacaHack

96 solves

last week

Compressor
Misc
Daily AlpacaHack

110 solves

last week

Pyrunner
Misc
Daily AlpacaHack B-SIDE

38 solves

last week

git gc
Misc
Daily AlpacaHack

154 solves

last week

shellcode-101
Pwn
Daily AlpacaHack

138 solves

last week

optimal-sort
Misc
Daily AlpacaHack

104 solves

last week

Linear Coffee Generator
Crypto
Daily AlpacaHack

115 solves

last week

Message For You
Web
Daily AlpacaHack

187 solves

last week

Plz Login
Web
Daily AlpacaHack

225 solves

last week

Alpaca-Llama Ranch
Pwn
Daily AlpacaHack

125 solves

last week

ToyPQC
Crypto
Daily AlpacaHack

108 solves

last week

AAAAAAAAEEEEEEEESSSSSSSS
Crypto
Daily AlpacaHack

121 solves

last week

Pickle Loader
Misc
Daily AlpacaHack

117 solves

last week

simple ROP
Pwn
Daily AlpacaHack

114 solves

last week

Disappeared
Pwn
Daily AlpacaHack

115 solves

last week

Dot Chain
Misc
Daily AlpacaHack

84 solves

last week

vuln4vuln
Pwn
Daily AlpacaHack

96 solves

last week

PPPPParse
Misc
Daily AlpacaHack

98 solves

last week

EncodeDecode
Misc
Daily AlpacaHack

85 solves

last week

Tar Uploader
Web
Daily AlpacaHack

100 solves

last week

Alpacker
Rev
Daily AlpacaHack

78 solves

last week

silence
Misc
Daily AlpacaHack

99 solves

last week

flag.txt
Misc
Daily AlpacaHack

110 solves

2 weeks ago

encrypted-p
Crypto
Daily AlpacaHack

100 solves

2 weeks ago

Flags for the FLAG
Misc
Daily AlpacaHack

149 solves

2 weeks ago

Free Coupon
Web
Daily AlpacaHack

135 solves

2 weeks ago

canary leak
Pwn
Daily AlpacaHack

106 solves

2 weeks ago

bloom
Crypto
Daily AlpacaHack

86 solves

2 weeks ago

What's Next
Web
Daily AlpacaHack

110 solves

2 weeks ago

crypto_666
Crypto
Daily AlpacaHack

105 solves

2 weeks ago

Optimized expression
Rev
Daily AlpacaHack

115 solves

2 weeks ago

The future path
Crypto
Daily AlpacaHack

92 solves

3 weeks ago

RANDOM IN THE FUTURE.
Crypto
tkbctf5

28 solves

4 weeks ago

guess.js
Misc
Daily AlpacaHack

103 solves

4 weeks ago

Heuristic IPPON
Misc
Daily AlpacaHack

167 solves

4 weeks ago

memset note
Pwn
Daily AlpacaHack B-SIDE

44 solves

last month

Another Login Challenge
Web
Daily AlpacaHack

123 solves

last month

iwashi
Crypto
Daily AlpacaHack B-SIDE

37 solves

last month

nc magic
Misc
Daily AlpacaHack

133 solves

last month

kappa overflow
Pwn
Daily AlpacaHack

121 solves

last month

high and low
Crypto
Daily AlpacaHack

87 solves

last month

Find XOR key
Crypto
Daily AlpacaHack

150 solves

last month

💯
Misc
Daily AlpacaHack

116 solves

last month

FLAG OVER
Misc
Daily AlpacaHack

115 solves

last month

misdirection
Rev
Daily AlpacaHack

161 solves

last month

destructuring
Misc
Daily AlpacaHack

143 solves

last month

magic number
Misc
Daily AlpacaHack

124 solves

last month

Alert my Flag
Web
Daily AlpacaHack

166 solves

last month

Flag Printer 2026
Misc
Daily AlpacaHack

204 solves

last month

glibc's secret function
Rev
Daily AlpacaHack

195 solves

last month

Bars
Web
Daily AlpacaHack

298 solves

last month

One Byte Padding Oracle Attack
Crypto
Daily AlpacaHack

74 solves

last month

Alpaca Rangers
Web
Daily AlpacaHack

148 solves

last month

hit-and-hit
Misc
Daily AlpacaHack

86 solves

last month

Noob programmer
Pwn
Daily AlpacaHack

105 solves

last month

Alpaillier
Crypto
Daily AlpacaHack

117 solves

last month

Alpaca Quest
Rev
Daily AlpacaHack

115 solves

last month

CopperCopperCopper
Crypto
Daily AlpacaHack

92 solves

last month

ECRSA
Crypto
Daily AlpacaHack B-SIDE

45 solves

last month

Dancing Cursor
RevMisc
Daily AlpacaHack

109 solves

last month

wages of sin()
RevMisc
Daily AlpacaHack

93 solves

last month

The World
Misc
Daily AlpacaHack

191 solves

2 months ago

RRe_Time_Limiter
Crypto
Daily AlpacaHack

177 solves

2 months ago

Magic Engine
Web
Daily AlpacaHack

271 solves

2 months ago

read-a-binary
Rev
Daily AlpacaHack

225 solves

2 months ago

Inu Profile
Web
Daily AlpacaHack B-SIDE

95 solves

2 months ago

Substance
Crypto
Daily AlpacaHack

240 solves

2 months ago

Stateless Auth
Web
Daily AlpacaHack

168 solves

2 months ago

Paca Paca Authenticator
Crypto
Daily AlpacaHack

127 solves

2 months ago

Bashrunner
Misc
Daily AlpacaHack

120 solves

2 months ago

Animal Viewer
Web
Daily AlpacaHack

154 solves

2 months ago

dockerstack
Misc
Daily AlpacaHack

180 solves

2 months ago

system-v
Rev
Daily AlpacaHack

118 solves

2 months ago

ChaChaCha
Crypto
Daily AlpacaHack

157 solves

2 months ago

dice roll
Web
Daily AlpacaHack

201 solves

2 months ago

Base Length
Misc
Daily AlpacaHack

157 solves

2 months ago

Short Writer
Pwn
Daily AlpacaHack

124 solves

2 months ago

Five Alpacas
Crypto
Daily AlpacaHack

196 solves

2 months ago

free-comment
Misc
Daily AlpacaHack

152 solves

2 months ago

I wanna be the Admin
Web
Daily AlpacaHack

283 solves

2 months ago

Basic Buffer Overflow
Pwn
Daily AlpacaHack

186 solves

2 months ago

crazython
Rev
Daily AlpacaHack

188 solves

3 months ago

RSA2026
Crypto
Daily AlpacaHack

209 solves

3 months ago

SwapSwap
Misc
Daily AlpacaHack

286 solves

3 months ago

secret-table
Web
Daily AlpacaHack

270 solves

3 months ago

Square RSA
Crypto
Daily AlpacaHack

235 solves

3 months ago

jailiaj
Misc
Daily AlpacaHack

281 solves

3 months ago

Encoding Basics
MiscCrypto
Daily AlpacaHack

317 solves

3 months ago

Fushigi Crawler
Web
Daily AlpacaHack

343 solves

3 months ago

Ruby Flag Checker
Rev
Daily AlpacaHack

289 solves

3 months ago

super-tomato
Crypto
Daily AlpacaHack

388 solves

3 months ago

RBG
Crypto
Daily AlpacaHack

123 solves

3 months ago

108
Misc
Daily AlpacaHack

296 solves

3 months ago

one-p-rsa
Crypto
Daily AlpacaHack

231 solves

3 months ago

cha-ll-enge
Rev
SECCON Beginners CTF 2024

158 solves

3 months ago

simpleoverwrite
Pwn
SECCON Beginners CTF 2024

197 solves

3 months ago

Useful Machine
Rev
Daily AlpacaHack

158 solves

3 months ago

Xmas Login
Web
Daily AlpacaHack

353 solves

3 months ago

cat3
Misc
Daily AlpacaHack

221 solves

3 months ago

Rotten Beef
Pwn
Daily AlpacaHack

204 solves

3 months ago

Log Viewer
Web
Daily AlpacaHack

225 solves

3 months ago

RSA debug?
Crypto
Daily AlpacaHack

192 solves

3 months ago

omikuji
Web
Daily AlpacaHack

249 solves

3 months ago

alloc-101
Pwn
Daily AlpacaHack

218 solves

3 months ago

Twilight
Rev
Daily AlpacaHack

230 solves

3 months ago

login-bonus
Pwn
Daily AlpacaHack

255 solves

3 months ago

🐈
Web
Daily AlpacaHack

309 solves

3 months ago

Flag Printer 2100
Rev
Daily AlpacaHack

246 solves

3 months ago

power_obfus_royalty
Rev
Daily AlpacaHack

209 solves

3 months ago

Safe Prime
Crypto
SECCON Beginners CTF 2024

253 solves

4 months ago

Sugoi Flag Checker
Rev
Daily AlpacaHack

204 solves

4 months ago

Alpaca Bank
Web
Daily AlpacaHack

331 solves

4 months ago

Read Assembly
Rev
Daily AlpacaHack

312 solves

4 months ago

hit-and-miss
Misc
Daily AlpacaHack

387 solves

4 months ago

Fully Padded RSA
Crypto
Daily AlpacaHack

237 solves

4 months ago

Integer Writer
Pwn
Daily AlpacaHack

325 solves

4 months ago

size limit
Crypto
Daily AlpacaHack

317 solves

4 months ago

Leaked Flag Checker
Rev
Daily AlpacaHack

567 solves

4 months ago

a fact of CTF
Crypto
Daily AlpacaHack

883 solves

4 months ago

Emojify
Web
Daily AlpacaHack

593 solves

4 months ago

AlpacaHack 2100
Misc
Daily AlpacaHack

1632 solves

4 months ago

simpleoverflow
Pwn
SECCON Beginners CTF 2024

505 solves

4 months ago

MissingNo.2
Crypto
AlpacaHack Round 13 (Crypto)

9 solves

8 months ago

MissingNo.1
Crypto
AlpacaHack Round 13 (Crypto)

11 solves

8 months ago

Polynomial Puzzle
Crypto
AlpacaHack Round 13 (Crypto)

5 solves

8 months ago

Jerr0-day
Crypto
AlpacaHack Round 13 (Crypto)

15 solves

8 months ago

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

33 solves

8 months ago

Zero-sum game
Crypto
AlpacaHack Round 12 (Crypto)

4 solves

9 months ago

Flag Sharing
Crypto
AlpacaHack Round 12 (Crypto)

10 solves

9 months ago

OTEC
Crypto
AlpacaHack Round 12 (Crypto)

39 solves

9 months ago

RSARSARSARSARSARSA
Crypto
AlpacaHack Round 12 (Crypto)

79 solves

9 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)

129 solves

last year

Treasure Hunt
Web
AlpacaHack Round 7 (Web)

271 solves

last year

SchnorrLCG
Crypto
AlpacaHack Round 5 (Crypto)

23 solves

last year

NNNN
Crypto
AlpacaHack Round 5 (Crypto)

50 solves

last year

XorshiftStream
Crypto
AlpacaHack Round 5 (Crypto)

65 solves

last year

Broadcasting NTRU
Crypto
AlpacaHack Round 5 (Crypto)

11 solves

last year

Simple Flag Checker
Rev
AlpacaHack Round 4 (Rev)

127 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)

253 solves

last year

echo
Pwn
AlpacaHack Round 1 (Pwn)

357 solves

last year

Pico Note 1
Web
AlpacaHack Round 2 (Web)

81 solves

last year

CaaS
Web
AlpacaHack Round 2 (Web)

93 solves

last year

Simple Login
Web
AlpacaHack Round 2 (Web)

611 solves

last year

Welcome
Misc

1544 solves

last year