CVEs-PoC/2021/CVE-2021-27291.md

### [CVE-2021-27291](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-27291)
![](https://img.shields.io/static/v1?label=Product&message=n%2Fa&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=n%2Fa%20&color=brightgreen)
![](https://img.shields.io/static/v1?label=Vulnerability&message=n%2Fa&color=brightgreen)

### Description

In pygments 1.1+, fixed in 2.7.4, the lexers used to parse programming languages rely heavily on regular expressions. Some of the regular expressions have exponential or cubic worst-case complexity and are vulnerable to ReDoS. By crafting malicious input, an attacker can cause a denial of service.

### POC

#### Reference
No PoCs from references.

#### Github
- https://github.com/ARPSyndicate/cvemon
- https://github.com/HotDB-Community/HotDB-Engine
- https://github.com/asa1997/topgear_test
- https://github.com/doyensec/regexploit
- https://github.com/engn33r/awesome-redos-security
- https://github.com/retr0-13/regexploit