CVEs-PoC/2020/CVE-2020-25683.md

### [CVE-2020-25683](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-25683)
![](https://img.shields.io/static/v1?label=Product&message=dnsmasq&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=n%2Fa&color=blue)
![](https://img.shields.io/static/v1?label=Vulnerability&message=CWE-122&color=brighgreen)

### Description

A flaw was found in dnsmasq before version 2.83. A heap-based buffer overflow was discovered in dnsmasq when DNSSEC is enabled and before it validates the received DNS entries. A remote attacker, who can create valid DNS replies, could use this flaw to cause an overflow in a heap-allocated memory. This flaw is caused by the lack of length checks in rfc1035.c:extract_name(), which could be abused to make the code execute memcpy() with a negative size in get_rdata() and cause a crash in dnsmasq, resulting in a denial of service. The highest threat from this vulnerability is to system availability.

### POC

#### Reference
No PoCs from references.

#### Github
- https://github.com/AZ-X/pique
- https://github.com/DNTYO/F5_Vulnerability
- https://github.com/kaosagnt/ansible-everyday
- https://github.com/klcheung99/CSCM28CW2