Removing the FBI MoneyPak Virus

The FBI MoneyPak virus is a form of ransomware that tricks unsuspecting victims into paying large sums of money ($200 at the time of this article's writing).

A walkthrough for io.smashthestack.org Level 1

Hello, in this tutorial I will show you how to defeat the security in the first level of the smashthestack io servers.  The program which we will be exploiting is set to always be run by the level2 user.  What this means is that if we are logged into a lower level account (level1) this program will be run in a process with higher privileges than our own.  So, if we can hijack the process, we can use it to retrieve the password for level2 from a new shell and therefore gain permanent access to the account.  This level is particularly easy because the program will automatically spawn a shell for you.  In most cases it's not this simple and will require using a buffer overflow to inject code into the process in order to achieve the desired effect.

Simple 8086 Assembly Bootloader

Using an assembler such as NASM, the following code could be used to create a bootloader for a PC:
It can be compiled into a floppy image through:
nasm filename.asm -f bin -o filename.img

[BITS 16] ;This code is 16-bit
[ORG 0x7C00] ;The code will initially be loaded at address 0x7C00 in RAM, the              ;location where the PC initially looks for executable code

main:
jmp $ ;Infinite Loop   

times 510-($-$$) db 0 ;The preceding code does not take up 512 bytes(a sector)                      ;this line tells the assembler to pad (510-CodeSize)                          ;bytes
dw 0xAA55 ;The hexidecimal bytes 0xAA & 0x55 are required in the last two bytes of the 512 byte sector in order for the BIOS to recognize this code as a bootloader.