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Daily AlpacaHack

A CTF challenge series with fun puzzles to enjoy every day

What is Daily AlpacaHack?

We regularly publish simple, beginner-friendly or educational CTF challenges!

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Solve each challenge within its time window to appear on the leaderboard.

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Today's Challenge
tan90909090tan90909090
integer division
Misc
Medium
27 solves
Submissions (latest 3)
blackade

SOLVED!

Sep 14, 5:14 AM

Leaderboard

Try the first challenge

Is this your first CTF? Let's begin by tackling the first challenge released on Daily AlpacaHack.

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admin
AlpacaHack 2100
Misc
Welcome🌱
2,201 solves
Upcoming challenges reveal the , , and in advance.
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Mar 2026

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23
kakur41kakur41
Alpaca Quest
Rev
Medium
136 solves
24
minaminaominaminao
hit-and-hit
Misc
Hard
91 solves
25
tchentchen
Alpaca Rangers
Web
Medium
213 solves
26
kurenaifkurenaif
27
tchentchen
28
minaminaominaminao
pyjs
Misc
Hard
89 solves
1
admin
Alpaca meets QR
Misc
Welcome🌱
366 solves
2
kakur41kakur41
Bars
Web
Easy🌱
447 solves
3
tan90909090tan90909090
glibc's secret function
Rev
Easy🌱
245 solves
4
minaminaominaminao
Flag Printer 2026
Misc
Easy🌱
261 solves
5
tchentchen
Alert my Flag
Web
Medium
236 solves
6
moramora
magic number
Misc
Medium
143 solves
7
theoremoontheoremoon
high and low
Crypto
Hard
94 solves
8
arkark
guess.js
Misc
Hard
113 solves
9
minaminaominaminao
FLAG OVER
Misc
Medium
127 solves
10
arkark
💯
Misc
Medium
134 solves
11
pppp4649pppp4649
Find XOR key
Crypto
Easy🌱
189 solves
12
colza
kappa overflow
Pwn
Medium
146 solves
13
tchentchen
Another Login Challenge
Web
Medium
173 solves
14
asusnasusn
Heuristic IPPON
Misc
Easy🌱
200 solves
15
minaminaominaminao
flag.txt
Misc
Hard
124 solves
16
pppp4649pppp4649
The future path
Crypto
Medium
100 solves
17
tchentchen
Free Coupon
Web
Medium
174 solves
18
arkark
PPPPParse
Misc
Medium
106 solves
19
rsk0315
Flags for the FLAG
Misc
Easy🌱
184 solves
20
colza
canary leak
Pwn
Medium
124 solves
21
chocoruskchocorusk
Alpacker
Rev
Hard
87 solves
22
k0080k0080
vuln4vuln
Pwn
Hard
110 solves
23
kanonkanon
bloom
Crypto
Medium
100 solves
24
tchentchen
What's Next
Web
Medium
132 solves
25
kurenaifkurenaif
crypto_666
Crypto
Medium
123 solves
26
tan90909090tan90909090
Optimized expression
Rev
Easy🌱
147 solves
27
minaminaominaminao
encrypted-p
Crypto
Medium
118 solves
28
hiikunzhiikunz
EncodeDecode
Misc
Hard
92 solves
29
tchentchen
Dot Chain
Misc
Hard
91 solves
30
tchentchen
Tar Uploader
Web
Medium
116 solves
31
blackade
silence
Misc
Medium
108 solves
1
admin
OSINT
Misc
Welcome🌱
448 solves
2
tchentchen
Message For You
Web
Easy🌱
324 solves
3
pppp4649pppp4649
You are my friend
Crypto
Easy🌱
243 solves
4
hiikunzhiikunz
Impossible Puzzle
Web
Easy🌱
288 solves
5
kanonkanon
The Horn
Crypto
Medium
116 solves

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