CVE-2019-3931 Explained : Impact and Mitigation

Devices such as the Crestron AM-100 running firmware version 1.6.0.2 and the Crestron AM-101 running firmware version 2.7.0.2 have a security vulnerability that can be exploited through argument injection in the curl binary by using specifically crafted HTTP requests to the return.cgi endpoint. An attacker who is remote and authenticated could potentially exploit this vulnerability to upload files onto the device and ultimately gain root-level access, thereby enabling them to execute arbitrary code.

Understanding CVE-2019-3931

This CVE identifies a security vulnerability in Crestron AirMedia devices with specific firmware versions.

What is CVE-2019-3931?

CVE-2019-3931 is a vulnerability that allows remote, authenticated attackers to upload files and execute arbitrary code on Crestron AM-100 and AM-101 devices.

The Impact of CVE-2019-3931

The exploitation of this vulnerability can lead to unauthorized file uploads and potential execution of malicious code with root-level access on the affected devices.

Technical Details of CVE-2019-3931

This section provides detailed technical information about the CVE.

Vulnerability Description

The vulnerability involves argument injection in the curl binary through crafted HTTP requests to the return.cgi endpoint on Crestron AirMedia devices.

Affected Systems and Versions

Product: Crestron AirMedia
Vendor: Crestron
Affected Versions: AM-100 firmware 1.6.0.2 and AM-101 firmware 2.7.0.2

Exploitation Mechanism

Attackers exploit the vulnerability by using specifically crafted HTTP requests to the return.cgi endpoint, allowing them to upload files and potentially execute arbitrary code.

Mitigation and Prevention

Protecting systems from CVE-2019-3931 requires immediate actions and long-term security practices.

Immediate Steps to Take

Update the firmware of Crestron AM-100 and AM-101 devices to versions that address this vulnerability.
Monitor network traffic for any suspicious activities that could indicate exploitation attempts.

Long-Term Security Practices

Regularly update firmware and software to patch known vulnerabilities.
Implement network segmentation to limit the impact of potential breaches.

Patching and Updates

Apply patches provided by Crestron to fix the vulnerability and enhance the security of the affected devices.