CVE-2020-8515 : What You Need to Know

DrayTek Vigor2960, Vigor3900, and Vigor300B devices were found to have a critical vulnerability that allowed remote code execution without authentication. This issue has been addressed in the latest firmware update.

Understanding CVE-2020-8515

This CVE identifies a severe security flaw in DrayTek networking devices that could be exploited by attackers to execute arbitrary code remotely.

What is CVE-2020-8515?

The vulnerability in DrayTek Vigor2960, Vigor3900, and Vigor300B devices enables attackers to execute commands as the root user without the need for authentication. By leveraging shell metacharacters in the cgi-bin/mainfunction.cgi URI, malicious actors can gain unauthorized access to the affected devices.

The Impact of CVE-2020-8515

The exploitation of this vulnerability could lead to severe consequences, including unauthorized access to sensitive information, manipulation of device settings, and potential network compromise.

Technical Details of CVE-2020-8515

DrayTek Vigor devices are susceptible to remote code execution due to improper input validation in the mainfunction.cgi URI.

Vulnerability Description

The flaw allows threat actors to inject and execute arbitrary commands on the affected devices, granting them unauthorized access and control.

Affected Systems and Versions

DrayTek Vigor2960 1.3.1_Beta
DrayTek Vigor3900 1.4.4_Beta
DrayTek Vigor300B 1.3.3_Beta, 1.4.2.1_Beta, and 1.4.4_Beta

Exploitation Mechanism

Attackers exploit shell metacharacters in the cgi-bin/mainfunction.cgi URI to execute commands as the root user without authentication.

Mitigation and Prevention

It is crucial to take immediate action to secure vulnerable DrayTek devices and prevent potential exploitation.

Immediate Steps to Take

Update affected devices to the latest firmware version (Vigor3900/2960/300B v1.5.1) to mitigate the vulnerability.
Implement strong network segmentation to limit the impact of potential attacks.
Monitor network traffic for any suspicious activities that may indicate exploitation attempts.

Long-Term Security Practices

Regularly update firmware and security patches to protect against known vulnerabilities.
Conduct security assessments and penetration testing to identify and address potential weaknesses in network devices.

Patching and Updates

DrayTek has released firmware updates that address the CVE-2020-8515 vulnerability. It is essential for users to promptly apply these patches to safeguard their devices against exploitation.