Leetius

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10 / 12 22949 / 51059


Using the Terminal

Time of First Successful Submission: 2026-06-30 23:12:02

Using the VSCode Workspace

Time of First Successful Submission: 2026-06-30 23:14:04

Using the GUI Desktop

Time of First Successful Submission: 2026-06-30 23:15:13

Pasting into the Desktop

Time of First Successful Submission: 2026-06-30 23:16:53

Restarting Challenges

Time of First Successful Submission: 2026-06-30 23:19:47

Challenge Programs

Time of First Successful Submission: 2026-06-30 23:24:31

The Flag File

Time of First Successful Submission: 2026-06-30 23:29:22

Using Privileged Mode

Time of First Successful Submission: 2026-06-30 23:33:11

Persistent Home Directories - One

Time of First Successful Submission: 2026-06-30 23:38:10

Persistent Home Directories - Two

Time of First Successful Submission: 2026-06-30 23:39:13


Linux Luminarium

1 / 128 37681 / 37691


grepping for a needle in a haystack

Time of First Successful Submission: 2026-07-12 14:09:02


Computing 101

132 / 132 41 / 21160


Your First Register

Time of First Successful Submission: 2026-07-01 00:27:46

Your First Syscall

Time of First Successful Submission: 2026-07-01 00:31:19

Exit Codes

Time of First Successful Submission: 2026-07-01 00:35:56

Building Executables

Time of First Successful Submission: 2026-07-01 00:58:09

Moving Between Registers

Time of First Successful Submission: 2026-07-01 01:04:33

Loading From Memory

Time of First Successful Submission: 2026-07-01 16:24:28

More Loading Practice

Time of First Successful Submission: 2026-07-01 16:26:32

Dereferencing Pointers

Time of First Successful Submission: 2026-07-01 16:38:32

Dereferencing Yourself

Time of First Successful Submission: 2026-07-01 16:42:55

Dereferencing with Offsets

Time of First Successful Submission: 2026-07-01 16:52:22

Stored Addresses

Time of First Successful Submission: 2026-07-01 17:00:33

Double Dereference

Time of First Successful Submission: 2026-07-01 17:36:03

The Stack

Time of First Successful Submission: 2026-07-01 17:46:03

Stack Offsets

Time of First Successful Submission: 2026-07-01 17:50:00

Program Arguments on the Stack

Time of First Successful Submission: 2026-07-01 18:04:10

Popping From the Stack

Time of First Successful Submission: 2026-07-01 18:36:38

Negative Numbers

Time of First Successful Submission: 2026-07-01 20:07:19

Negative Numbers (16-bit)

Time of First Successful Submission: 2026-07-01 20:23:39

Negative Numbers (32-bit)

Time of First Successful Submission: 2026-07-01 20:26:35

Encoding Negatives

Time of First Successful Submission: 2026-07-01 20:31:42

Binary and Hex Encoding

Time of First Successful Submission: 2026-07-01 20:38:15

More Hex

Time of First Successful Submission: 2026-07-01 20:48:17

Decoding Hex

Time of First Successful Submission: 2026-07-01 20:51:05

Mixed Conversions

Time of First Successful Submission: 2026-07-01 21:02:49

Disassembling Programs

Time of First Successful Submission: 2026-07-01 21:59:27

Tracing Syscalls

Time of First Successful Submission: 2026-07-01 22:19:47

Starting GDB

Time of First Successful Submission: 2026-07-01 23:01:16

Quitting GDB

Time of First Successful Submission: 2026-07-01 23:09:08

Starting Programs in GDB

Time of First Successful Submission: 2026-07-01 23:12:25

Disassembling in GDB

Time of First Successful Submission: 2026-07-01 23:16:54

Stepping Through Instructions

Time of First Successful Submission: 2026-07-01 23:22:37

Reading Register Values

Time of First Successful Submission: 2026-07-01 23:30:30

Setting Register Values

Time of First Successful Submission: 2026-07-11 22:00:37

Popping Stack Values

Time of First Successful Submission: 2026-07-01 23:38:46

Examining Memory

Time of First Successful Submission: 2026-07-01 23:46:36

Examining Stack Pointers

Time of First Successful Submission: 2026-07-01 23:55:49

Cooperative Debugging

Time of First Successful Submission: 2026-07-02 00:21:17

Running with Arguments

Time of First Successful Submission: 2026-07-02 00:30:57

Redirecting Input in GDB

Time of First Successful Submission: 2026-07-02 00:39:37

Writing Output

Time of First Successful Submission: 2026-07-02 17:35:34

Chaining Syscalls

Time of First Successful Submission: 2026-07-02 18:12:48

Writing Strings

Time of First Successful Submission: 2026-07-02 18:15:37

Reading Data

Time of First Successful Submission: 2026-07-02 18:47:25

Reading Exactly

Time of First Successful Submission: 2026-07-02 19:21:23

Opening Files

Time of First Successful Submission: 2026-07-02 19:45:52

Hardcoding the Filename

Time of First Successful Submission: 2026-07-02 20:25:33

RIP-Relative Strings

Time of First Successful Submission: 2026-07-02 21:33:57

Comparing Values

Time of First Successful Submission: 2026-07-02 22:41:31

Comparing Characters

Time of First Successful Submission: 2026-07-02 23:08:46

Conditional Control Flow

Time of First Successful Submission: 2026-07-02 23:26:55

Comparing Strings

Time of First Successful Submission: 2026-07-02 23:56:53

Reverse the Password

Time of First Successful Submission: 2026-07-03 00:08:57

Conditionals Without Conditionals

Time of First Successful Submission: 2026-07-03 01:46:07

Recognizing Loops

Time of First Successful Submission: 2026-07-04 22:20:28

Writing Loops

Time of First Successful Submission: 2026-07-09 20:48:06

Writing From a Shared Library

Time of First Successful Submission: 2026-07-04 23:00:57

Returning a Value

Time of First Successful Submission: 2026-07-04 23:20:06

Calling Through a Pointer

Time of First Successful Submission: 2026-07-04 23:30:57

Calling Through a Pointer with an Argument

Time of First Successful Submission: 2026-07-04 23:40:02

Saving Caller-Saved Registers

Time of First Successful Submission: 2026-07-04 23:59:13

Saving Callee-Saved Registers

Time of First Successful Submission: 2026-07-05 00:16:15

Sign Extension

Time of First Successful Submission: 2026-07-05 01:06:51

Little-Endian Bytes

Time of First Successful Submission: 2026-07-05 01:14:09

Qword by Qword

Time of First Successful Submission: 2026-07-05 01:33:28

Dword by Dword

Time of First Successful Submission: 2026-07-05 02:30:55

Word by Word

Time of First Successful Submission: 2026-07-05 15:21:03

Byte by Byte

Time of First Successful Submission: 2026-07-05 15:24:10

Cracking a Struct

Time of First Successful Submission: 2026-07-05 15:48:15

Scrambled Struct

Time of First Successful Submission: 2026-07-05 16:08:00

Reverse the Calculation

Time of First Successful Submission: 2026-07-05 16:42:26

Reverse the Reverse

Time of First Successful Submission: 2026-07-05 16:50:13

Dealing with Bitwise Operations

Time of First Successful Submission: 2026-07-05 17:07:56

Even or Odd

Time of First Successful Submission: 2026-07-05 17:29:00

Masking Bits

Time of First Successful Submission: 2026-07-05 17:36:37

Lowercase a String

Time of First Successful Submission: 2026-07-05 22:53:34

Uppercase a String

Time of First Successful Submission: 2026-07-05 23:06:21

Swap Case

Time of First Successful Submission: 2026-07-05 23:22:07

Shifting Left

Time of First Successful Submission: 2026-07-05 23:52:17

Shifting Right

Time of First Successful Submission: 2026-07-06 00:04:40

Loops on Data

Time of First Successful Submission: 2026-07-06 00:17:26

Reaching Into the Caller's Frame

Time of First Successful Submission: 2026-07-06 15:25:07

Loading Stale Stack Data

Time of First Successful Submission: 2026-07-06 15:57:13

Stealing Stale Stack Data

Time of First Successful Submission: 2026-07-06 17:42:24

Reserving Your Own Frame

Time of First Successful Submission: 2026-07-06 18:33:54

Using Your Own Frame

Time of First Successful Submission: 2026-07-06 20:23:41

Environment Variables on the Stack

Time of First Successful Submission: 2026-07-06 21:27:16

Aligning the Stack Through the Environment

Time of First Successful Submission: 2026-07-06 21:35:04

Aligning the Stack Through GDB

Time of First Successful Submission: 2026-07-06 21:50:37

Aligning the Stack Through GDB, Generalized

Time of First Successful Submission: 2026-07-06 21:57:09

A Single Digit

Time of First Successful Submission: 2026-07-06 22:39:26

Two Digits

Time of First Successful Submission: 2026-07-06 23:47:27

String to Integer

Time of First Successful Submission: 2026-07-07 16:07:31

Negative Numbers

Time of First Successful Submission: 2026-07-07 17:19:41

Where the Number Ends

Time of First Successful Submission: 2026-07-07 19:06:46

A Whole Program

Time of First Successful Submission: 2026-07-07 19:22:31

A Single Digit, Back to Text

Time of First Successful Submission: 2026-07-07 20:35:41

Divide and Remainder

Time of First Successful Submission: 2026-07-07 20:32:47

Drop the Leading Zero

Time of First Successful Submission: 2026-07-07 20:41:56

Integer to String

Time of First Successful Submission: 2026-07-07 21:32:20

Negative Numbers, Back to Text

Time of First Successful Submission: 2026-07-07 22:54:29

Sum Them All

Time of First Successful Submission: 2026-07-08 01:15:38

Addition

Time of First Successful Submission: 2026-07-08 22:38:18

Subtraction

Time of First Successful Submission: 2026-07-08 22:48:54

Multiplication

Time of First Successful Submission: 2026-07-08 22:55:32

Bitwise Operators

Time of First Successful Submission: 2026-07-08 23:12:01

Unary Operators

Time of First Successful Submission: 2026-07-08 23:38:51

Literal Output

Time of First Successful Submission: 2026-07-09 00:28:37

Newline Escapes

Time of First Successful Submission: 2026-07-09 15:23:43

Escaped Syntax

Time of First Successful Submission: 2026-07-09 15:46:07

Decimal Markers

Time of First Successful Submission: 2026-07-09 17:08:09

Multiple Decimal Markers

Time of First Successful Submission: 2026-07-09 18:10:32

String Markers

Time of First Successful Submission: 2026-07-09 18:38:02

Hex Byte Escapes

Time of First Successful Submission: 2026-07-09 20:01:58

Debugging Programs

Time of First Successful Submission: 2026-07-09 23:39:41

Inspecting Registers

Time of First Successful Submission: 2026-07-09 23:51:01

Examining Memory

Time of First Successful Submission: 2026-07-10 00:07:56

Setting Breakpoints

Time of First Successful Submission: 2026-07-10 00:46:02

GDB Scripting

Time of First Successful Submission: 2026-07-11 20:18:46

Modifying Data

Time of First Successful Submission: 2026-07-15 21:40:25

Modifying Execution

Time of First Successful Submission: 2026-07-11 20:21:45

Broken Functions

Time of First Successful Submission: 2026-07-11 21:43:36

Exit

Time of First Successful Submission: 2026-07-12 13:57:06

Socket

Time of First Successful Submission: 2026-07-12 15:17:04

Bind

Time of First Successful Submission: 2026-07-12 16:21:54

Listen

Time of First Successful Submission: 2026-07-12 16:48:44

Accept

Time of First Successful Submission: 2026-07-12 17:01:32

Static Response

Time of First Successful Submission: 2026-07-13 18:19:45

Dynamic Response

Time of First Successful Submission: 2026-07-13 23:18:58

Iterative GET Server

Time of First Successful Submission: 2026-07-13 23:23:19

Concurrent GET Server

Time of First Successful Submission: 2026-07-14 00:19:53

Concurrent POST Server

Time of First Successful Submission: 2026-07-14 01:47:27

Web Server

Time of First Successful Submission: 2026-07-15 21:23:02


Playing With Programs

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What's the password?

Time of First Successful Submission: 2026-07-12 20:36:52

... and again!

Time of First Successful Submission: 2026-07-12 20:42:34

Newline Troubles

Time of First Successful Submission: 2026-07-12 20:46:15

Reasoning about files

Time of First Successful Submission: 2026-07-12 21:13:06

Specifying Filenames

Time of First Successful Submission: 2026-07-12 21:15:29

Binary and Hex Encoding

Time of First Successful Submission: 2026-07-12 21:53:13

More Hex

Time of First Successful Submission: 2026-07-13 00:11:20

Decoding Hex

Time of First Successful Submission: 2026-07-12 23:16:52

Decoding Practice

Time of First Successful Submission: 2026-07-13 00:57:44

Encoding Practice

Time of First Successful Submission: 2026-07-13 01:10:10

Hex-encoding ASCII

Time of First Successful Submission: 2026-07-13 01:36:50

Nested Encoding

Time of First Successful Submission: 2026-07-13 15:31:36

Hex-encoding UTF-8

Time of First Successful Submission: 2026-07-13 15:37:52

UTF Mixups

Time of First Successful Submission: 2026-07-13 17:02:20

Modifying Encoded Data

Time of First Successful Submission: 2026-07-15 22:07:42

Decoding Base64

Time of First Successful Submission: 2026-07-15 22:23:27

Encoding Base64

Time of First Successful Submission: 2026-07-15 22:49:32

Dealing with Obfuscation

Time of First Successful Submission: 2026-07-15 22:49:03

Dealing with Obfuscation 2

Time of First Successful Submission: 2026-07-15 23:06:31


DSU Cyber Camps

10 / 104 23100 / 51365


Using the Terminal

Time of First Successful Submission: 2026-06-30 23:12:02

Using the VSCode Workspace

Time of First Successful Submission: 2026-06-30 23:14:04

Using the GUI Desktop

Time of First Successful Submission: 2026-06-30 23:15:13

Pasting into the Desktop

Time of First Successful Submission: 2026-06-30 23:16:53

Restarting Challenges

Time of First Successful Submission: 2026-06-30 23:19:47

Challenge Programs

Time of First Successful Submission: 2026-06-30 23:24:31

The Flag File

Time of First Successful Submission: 2026-06-30 23:29:22

Using Privileged Mode

Time of First Successful Submission: 2026-06-30 23:33:11

Persistent Home Directories - One

Time of First Successful Submission: 2026-06-30 23:38:10

Persistent Home Directories - Two

Time of First Successful Submission: 2026-06-30 23:39:13


GCA CTF

10 / 104 23100 / 51365


Using the Terminal

Time of First Successful Submission: 2026-06-30 23:12:02

Using the VSCode Workspace

Time of First Successful Submission: 2026-06-30 23:14:04

Using the GUI Desktop

Time of First Successful Submission: 2026-06-30 23:15:13

Pasting into the Desktop

Time of First Successful Submission: 2026-06-30 23:16:53

Restarting Challenges

Time of First Successful Submission: 2026-06-30 23:19:47

Challenge Programs

Time of First Successful Submission: 2026-06-30 23:24:31

The Flag File

Time of First Successful Submission: 2026-06-30 23:29:22

Using Privileged Mode

Time of First Successful Submission: 2026-06-30 23:33:11

Persistent Home Directories - One

Time of First Successful Submission: 2026-06-30 23:38:10

Persistent Home Directories - Two

Time of First Successful Submission: 2026-06-30 23:39:13