cve/2018/CVE-2018-20164.md

### [CVE-2018-20164](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-20164)
![](https://img.shields.io/static/v1?label=Product&message=n%2Fa&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=n%2Fa&color=blue)
![](https://img.shields.io/static/v1?label=Vulnerability&message=n%2Fa&color=brighgreen)

### Description

An issue was discovered in regex.yaml (aka regexes.yaml) in UA-Parser UAP-Core before 0.6.0. A Regular Expression Denial of Service (ReDoS) issue allows remote attackers to overload a server by setting the User-Agent header in an HTTP(S) request to a value containing a long digit string. (The UAP-Core project contains the vulnerability, propagating to all implementations.)

### POC

#### Reference
- https://www.x41-dsec.de/lab/advisories/x41-2018-009-uaparser/

#### Github
- https://github.com/engn33r/awesome-redos-security
- https://github.com/ossf-cve-benchmark/CVE-2018-20164