CVEs-PoC/2020/CVE-2020-6806.md

### [CVE-2020-6806](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-6806)
![](https://img.shields.io/static/v1?label=Product&message=Firefox%20ESR&color=blue)
![](https://img.shields.io/static/v1?label=Product&message=Firefox&color=blue)
![](https://img.shields.io/static/v1?label=Product&message=Thunderbird&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=%3C%2068.6%20&color=brighgreen)
![](https://img.shields.io/static/v1?label=Version&message=%3C%2074%20&color=brighgreen)
![](https://img.shields.io/static/v1?label=Vulnerability&message=BodyStream%3A%3AOnInputStreamReady%20was%20missing%20protections%20against%20state%20confusion&color=brighgreen)

### Description

By carefully crafting promise resolutions, it was possible to cause an out-of-bounds read off the end of an array resized during script execution. This could have led to memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 68.6, Firefox < 74, Firefox < ESR68.6, and Firefox ESR < 68.6.

### POC

#### Reference
- http://packetstormsecurity.com/files/157524/Firefox-js-ReadableStreamCloseInternal-Out-Of-Bounds-Access.html
- https://usn.ubuntu.com/4328-1/

#### Github
- https://github.com/ARPSyndicate/cvemon