### [CVE-2015-7853](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-7853)
![](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

The datalen parameter in the refclock driver in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to execute arbitrary code or cause a denial of service (crash) via a negative input value.

### POC

#### Reference
- http://packetstormsecurity.com/files/134082/FreeBSD-Security-Advisory-ntp-Authentication-Bypass.html
- http://packetstormsecurity.com/files/134137/Slackware-Security-Advisory-ntp-Updates.html

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