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Start Here

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Using the Terminal

Time of First Successful Submission: 2026-02-17 21:01:23

Challenge Programs

Time of First Successful Submission: 2026-02-17 21:05:22

The Flag File

Time of First Successful Submission: 2026-02-17 21:07:36

Using Privileged Mode

Time of First Successful Submission: 2026-02-17 21:15:35

Computing 101

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Your First Register

Time of First Successful Submission: 2026-02-17 21:34:35

Your First Syscall

Time of First Successful Submission: 2026-02-17 21:36:02

Exit Codes

Time of First Successful Submission: 2026-02-17 21:46:10

Building Executables

Time of First Successful Submission: 2026-02-18 00:27:36

Moving Between Registers

Time of First Successful Submission: 2026-02-17 22:13:56

Loading From Memory

Time of First Successful Submission: 2026-02-17 23:38:30

More Loading Practice

Time of First Successful Submission: 2026-02-17 23:40:48

Dereferencing Pointers

Time of First Successful Submission: 2026-02-17 23:45:28

Dereferencing Yourself

Time of First Successful Submission: 2026-02-17 23:48:39

Dereferencing with Offsets

Time of First Successful Submission: 2026-02-17 23:51:24

Stored Addresses

Time of First Successful Submission: 2026-02-18 00:09:11

Double Dereference

Time of First Successful Submission: 2026-02-18 00:17:12

The Stack

Time of First Successful Submission: 2026-02-18 00:35:11

Stack Offsets

Time of First Successful Submission: 2026-02-18 00:38:32

Program Arguments on the Stack

Time of First Successful Submission: 2026-02-18 00:46:06

Popping From the Stack

Time of First Successful Submission: 2026-02-18 00:55:00

Disassembling Programs

Time of First Successful Submission: 2026-02-18 22:19:40

Tracing Syscalls

Time of First Successful Submission: 2026-02-18 23:09:52

Starting GDB

Time of First Successful Submission: 2026-02-18 23:11:50

Quitting GDB

Time of First Successful Submission: 2026-02-18 23:12:36

Starting Programs in GDB

Time of First Successful Submission: 2026-02-18 23:39:24

Disassembling in GDB

Time of First Successful Submission: 2026-02-18 23:41:10

Stepping Through Instructions

Time of First Successful Submission: 2026-02-18 23:49:19

Reading Register Values

Time of First Successful Submission: 2026-02-18 23:50:31

Popping Stack Values

Time of First Successful Submission: 2026-02-18 23:56:57

Examining Memory

Time of First Successful Submission: 2026-02-19 00:01:41

Examining Stack Pointers

Time of First Successful Submission: 2026-02-19 00:07:43

Cooperative Debugging

Time of First Successful Submission: 2026-02-19 00:22:32

Writing Output

Time of First Successful Submission: 2026-02-19 02:44:02

Chaining Syscalls

Time of First Successful Submission: 2026-02-19 02:45:52

Writing Strings

Time of First Successful Submission: 2026-02-19 02:57:13

Reading Data

Time of First Successful Submission: 2026-02-19 03:50:11

Opening Files

Time of First Successful Submission: 2026-02-19 04:02:36

Hardcoding the Filename

Time of First Successful Submission: 2026-02-19 04:14:06

Comparing Values

Time of First Successful Submission: 2026-02-19 05:51:36

Comparing Characters

Time of First Successful Submission: 2026-02-19 06:11:54

Conditional Control Flow

Time of First Successful Submission: 2026-02-19 23:58:25

Reverse the Password

Time of First Successful Submission: 2026-02-20 02:23:17

Conditionals Without Conditionals

Time of First Successful Submission: 2026-02-22 22:10:12

Looping

Time of First Successful Submission: 2026-02-22 22:18:10

Reverse the Calculation

Time of First Successful Submission: 2026-02-23 01:00:25

Reverse the Reverse

Time of First Successful Submission: 2026-02-23 01:11:43

Dealing with Bitwise Operations

Time of First Successful Submission: 2026-02-23 01:53:52

Loops on Data

Time of First Successful Submission: 2026-02-23 01:56:23

set-register

Time of First Successful Submission: 2026-02-23 02:07:10

set-multiple-registers

Time of First Successful Submission: 2026-02-23 02:10:43

add-to-register

Time of First Successful Submission: 2026-02-23 02:13:32

linear-equation-registers

Time of First Successful Submission: 2026-02-23 02:17:15

integer-division

Time of First Successful Submission: 2026-02-23 03:35:14

modulo-operation

Time of First Successful Submission: 2026-02-23 03:37:12

set-upper-byte

Time of First Successful Submission: 2026-02-23 06:11:51

efficient-modulo

Time of First Successful Submission: 2026-02-23 18:39:50

byte-extraction

Time of First Successful Submission: 2026-02-23 19:22:55

bitwise-and

Time of First Successful Submission: 2026-02-23 20:06:52

check-even

Time of First Successful Submission: 2026-02-23 20:55:32

memory-read

Time of First Successful Submission: 2026-02-23 21:02:46

memory-write

Time of First Successful Submission: 2026-02-23 21:21:29

memory-increment

Time of First Successful Submission: 2026-02-23 21:27:29

byte-access

Time of First Successful Submission: 2026-02-23 21:33:24

memory-size-access

Time of First Successful Submission: 2026-02-23 22:01:28

little-endian-write

Time of First Successful Submission: 2026-02-23 22:30:37

memory-sum

Time of First Successful Submission: 2026-02-23 22:55:47

stack-subtraction

Time of First Successful Submission: 2026-02-23 23:02:37

swap-stack-values

Time of First Successful Submission: 2026-02-23 23:12:23

average-stack-values

Time of First Successful Submission: 2026-02-23 23:21:02

absolute-jump

Time of First Successful Submission: 2026-02-23 23:34:16

relative-jump

Time of First Successful Submission: 2026-02-23 23:44:43

jump-trampoline

Time of First Successful Submission: 2026-02-24 01:26:22

conditional-jump

Time of First Successful Submission: 2026-02-25 19:49:17

indirect-jump

Time of First Successful Submission: 2026-02-25 20:43:36

average-loop

Time of First Successful Submission: 2026-02-25 23:18:10

count-non-zero

Time of First Successful Submission: 2026-02-25 23:24:10

Playing With Programs

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What's the password?

Time of First Successful Submission: 2026-02-26 19:24:07

... and again!

Time of First Successful Submission: 2026-02-26 19:24:53

Newline Troubles

Time of First Successful Submission: 2026-02-26 19:31:03

Reasoning about files

Time of First Successful Submission: 2026-02-26 19:32:37

Specifying Filenames

Time of First Successful Submission: 2026-02-26 19:35:57

Binary and Hex Encoding

Time of First Successful Submission: 2026-02-26 21:34:37

More Hex

Time of First Successful Submission: 2026-02-26 21:41:36

Decoding Hex

Time of First Successful Submission: 2026-03-02 06:42:14

Decoding Practice

Time of First Successful Submission: 2026-03-03 02:33:56

Encoding Practice

Time of First Successful Submission: 2026-03-03 05:06:23

GCA CTF

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Using the Terminal

Time of First Successful Submission: 2026-02-17 21:01:23

Challenge Programs

Time of First Successful Submission: 2026-02-17 21:05:22

The Flag File

Time of First Successful Submission: 2026-02-17 21:07:36

Using Privileged Mode

Time of First Successful Submission: 2026-02-17 21:15:35