# Dirty Cow

## Overview

The **Dirty COW** vulnerability is an interesting case of the race condition vulnerability. It existed in the Linux kernel since September 2007, and was discovered and exploited in October 2016. **The vulnerability affects all Linux-based OS, including Android,** and its consequence is severe: attackers can gain root privilege by exploiting the vulnerability. The vulnerability resides in the code of **copy-on-write (COW)** inside Linux kernel. By exploiting this vulnerability, attackers can modify any protected file, even though these files are only readable.

## mmap()

## MAP\_SHARED, MAP\_PRIVATE and Copy On Write

## Discard the Copied Memory

## Mapping Read-Only Files

## The Dirty COW Vulnerability
