CVE-2021-28816 Explained : Impact and Mitigation

A stack buffer overflow vulnerability has been reported to affect QNAP devices running QTS, QuTScloud, and QuTS hero. This vulnerability allows attackers to execute arbitrary code. Read on to learn more about CVE-2021-28816 and how to mitigate the risks.

Understanding CVE-2021-28816

CVE-2021-28816 is a stack buffer overflow vulnerability impacting QNAP's QTS, QuTScloud, and QuTS hero. It was discovered by Bingwei Peng of VARAS@IIE and has a CVSS v3.1 base score of 7.6, indicating a high severity issue with a low attack complexity.

What is CVE-2021-28816?

This CVE involves a stack buffer overflow vulnerability that affects QNAP devices. If exploited, attackers can run arbitrary code, potentially leading to a compromise of the affected systems.

The Impact of CVE-2021-28816

The impact of this vulnerability is significant, with a CVSS v3.1 base score of 7.6 (High). Attackers can exploit this issue to execute malicious code on vulnerable devices, posing a risk to confidentiality, integrity, and availability.

Technical Details of CVE-2021-28816

The vulnerability allows attackers to trigger a stack buffer overflow, enabling the execution of arbitrary code on affected QNAP devices.

Vulnerability Description

The stack buffer overflow vulnerability in QTS, QuTScloud, and QuTS hero devices allows threat actors to execute arbitrary code, putting sensitive data and system availability at risk.

Affected Systems and Versions

QTS versions less than 4.5.4.1715 build 20210630, 5.0.0.1716 build 20210701, 4.3.3.1693 build 20210624, and 4.3.6.1750 build 20210730
QuTScloud version c4.5.6.1755
QuTS hero version h4.5.4.1771 build 20210825

Exploitation Mechanism

Attackers can exploit this vulnerability via a network-based attack with low complexity, requiring no user interaction to trigger the buffer overflow.

Mitigation and Prevention

It is crucial to take immediate steps to address CVE-2021-28816 to prevent potential exploitation and secure your QNAP devices.

Immediate Steps to Take

Update your QTS, QuTScloud, and QuTS hero devices to the fixed versions provided by QNAP: QTS 4.5.4.1715 build 20210630 or later, QTS 5.0.0.1716 build 20210701 or later, QTS 4.3.3.1693 build 20210624 or later, QTS 4.3.6.1750 build 20210730 or later, QuTScloud c4.5.6.1755 or later, QuTS hero h4.5.4.1771 build 20210825 or later.

Long-Term Security Practices

Regularly patch and update your QNAP devices to safeguard against known vulnerabilities and ensure the overall security of your systems.

Patching and Updates

Stay informed about security advisories from QNAP and promptly apply patches to address newly identified vulnerabilities and protect your devices.