### [CVE-2017-5419](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-5419)
![](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=unspecified%20&color=brightgreen)
![](https://img.shields.io/static/v1?label=Vulnerability&message=Repeated%20authentication%20prompts%20lead%20to%20DOS%20attack&color=brightgreen)

### Description

If a malicious site repeatedly triggers a modal authentication prompt, eventually the browser UI will become non-responsive, requiring shutdown through the operating system. This is a denial of service (DOS) attack. This vulnerability affects Firefox < 52 and Thunderbird < 52.

### POC

#### Reference
- https://www.mozilla.org/security/advisories/mfsa2017-05/

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