### [CVE-2015-4021](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-4021)
![](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 phar_parse_tarfile function in ext/phar/tar.c in PHP before 5.4.41, 5.5.x before 5.5.25, and 5.6.x before 5.6.9 does not verify that the first character of a filename is different from the \0 character, which allows remote attackers to cause a denial of service (integer underflow and memory corruption) via a crafted entry in a tar archive.

### POC

#### Reference
- http://www.oracle.com/technetwork/topics/security/linuxbulletinjan2016-2867209.html
- https://bugs.php.net/bug.php?id=69453
- https://hackerone.com/reports/104027

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