Firefox 66.0.1 Released with Fix for Critical Security Vulnerabilities that discovered via Trend Micro’s Zero Day Initiative. The vulnerability affects all the versions of Firefox below 66.0.1.

An attacker could exploit these vulnerabilities to take complete control over the target system of the process.

CVE-2019-9810: Incorrect alias information

Incorrect alias information with IonMonkey JIT compiler for Array.prototype.slice leads to missing bounds check and a buffer overflow.

The bounds checking is a method used for detecting the variable is present within the bounds, a failed bound check would through the exception and results in security vulnerabilities.

CVE-2019-9813: Ionmonkey type confusion with proto mutations

Mishandling of proto mutations leads to the type of confusion vulnerability in IonMonkey JIT code.

The type confusion vulnerability occurs, when the code doesn’t verify what objects it is passed to, and blindly uses it without type-checking.

By exploiting this vulnerability an attacker can execute arbitrary commands or code on a target machine or in a target process without user interaction.

This vulnerability discovered by an independent researcher Niklas Baumstark targeting Mozilla Firefox with a sandbox escape in Trend Micro Zero-day initiative contest and he successfully demonstrates the JIT bug in Firefox, for that he earned $40,000.

In Pwn2Own 2019 contents researchers exploit multiple bugs with leading providers such as Edge, Mozilla Firefox, Windows, VMware and earned $270,000 USD in a single day by submitting 9 unique zero-day exploits.

The Firefox bug was introduced in the second day of the contest by Fluoroacetate team and an individual security researcher Niklas Baumstark.