### [CVE-2015-7550](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-7550)
![](https://img.shields.io/static/v1?label=Product&message=n%2Fa&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=%3D%20n%2Fa%20&color=brighgreen)
![](https://img.shields.io/static/v1?label=Vulnerability&message=n%2Fa&color=brighgreen)

### Description

The keyctl_read_key function in security/keys/keyctl.c in the Linux kernel before 4.3.4 does not properly use a semaphore, which allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact via a crafted application that leverages a race condition between keyctl_revoke and keyctl_read calls.

### POC

#### Reference
- http://www.ubuntu.com/usn/USN-2890-3

#### Github
- https://github.com/wcventure/PERIOD