Is CVE-2021-34346 actively exploited?

No active exploitation of CVE-2021-34346 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2021-34346 be exploited remotely?

Yes. CVE-2021-34346 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2021-34346?

CVE-2021-34346 has a CVSS score of 9.8 (CRITICAL).

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CRITICAL

CVE-2021-34346

CWE-787Published: September 10, 2021· Updated: Jun 17, 2026

9.8

CVSS v3.1

Official Description

A stack buffer overflow vulnerability has been reported to affect QNAP device running NVR Storage Expansion. If exploited, this vulnerability allows attackers to execute arbitrary code. We have already fixed this vulnerability in the following versions of NVR Storage Expansion: NVR Storage Expansion 1.0.6 ( 2021/08/03 ) and later

NVD Source

Technical Analysis

CVE-2021-34346 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 9.8.

From a weakness classification perspective (CWE-787): Out-of-bounds write vulnerabilities can lead to data corruption, crashes, or arbitrary code execution.