Is CVE-2021-20700 actively exploited?

No active exploitation of CVE-2021-20700 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2021-20700 be exploited remotely?

Yes. CVE-2021-20700 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2021-20700?

CVE-2021-20700 has a CVSS score of 9.8 (CRITICAL).

HOME VULNERABILITIESCVE-2021-20700

CRITICAL

CVE-2021-20700

CWE-120Published: November 3, 2021· Updated: Jun 17, 2026

9.8

CVSS v3.1

Official Description

Buffer overflow vulnerability in the Disk Agent CLUSTERPRO X 4.3 for Windows and earlier, EXPRESSCLUSTER X 4.3 for Windows and earlier, CLUSTERPRO X 4.3 SingleServerSafe for Windows and earlier, EXPRESSCLUSTER X 4.3 SingleServerSafe for Windows and earlier allows attacker to remote code execution via a network.

NVD Source

Technical Analysis

CVE-2021-20700 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.