cve/2017/CVE-2017-5439.md

### [CVE-2017-5439](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-5439)
![](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%2045.9%20&color=brighgreen)
![](https://img.shields.io/static/v1?label=Version&message=%3C%2052.1%20&color=brighgreen)
![](https://img.shields.io/static/v1?label=Version&message=%3C%2053%20&color=brighgreen)
![](https://img.shields.io/static/v1?label=Vulnerability&message=Use-after-free%20in%20nsTArray%20Length()%20during%20XSLT%20processing&color=brighgreen)

### Description

A use-after-free vulnerability during XSLT processing due to poor handling of template parameters. This results in a potentially exploitable crash. This vulnerability affects Thunderbird < 52.1, Firefox ESR < 45.9, Firefox ESR < 52.1, and Firefox < 53.

### POC

#### Reference
- https://bugzilla.mozilla.org/show_bug.cgi?id=1336830
- https://www.mozilla.org/security/advisories/mfsa2017-12/

#### Github
No PoCs found on GitHub currently.