CVEs-PoC/2021/CVE-2021-22547.md

### [CVE-2021-22547](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-22547)
![](https://img.shields.io/static/v1?label=Product&message=Google%20Cloud%20IoT%20Device%20SDK%20for%20Embedded%20C&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=unspecified%20&color=brightgreen)
![](https://img.shields.io/static/v1?label=Vulnerability&message=CWE-120%20Buffer%20Overflow&color=brightgreen)

### Description

In IoT Devices SDK, there is an implementation of calloc() that doesn't have a length check. An attacker could pass in memory objects larger than the buffer and wrap around to have a smaller buffer than required, allowing the attacker access to the other parts of the heap. We recommend upgrading the Google Cloud IoT Device SDK for Embedded C used to 1.0.3 or greater.

### POC

#### Reference
- https://github.com/GoogleCloudPlatform/iot-device-sdk-embedded-c/blob/master/RELEASE-NOTES.md
- https://github.com/GoogleCloudPlatform/iot-device-sdk-embedded-c/pull/119

#### Github
- https://github.com/jornverhoeven/adrian