Is CVE-2021-33527 actively exploited?

No active exploitation of CVE-2021-33527 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2021-33527 be exploited remotely?

Yes. CVE-2021-33527 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2021-33527?

CVE-2021-33527 has a CVSS score of 9.8 (CRITICAL).

HOME VULNERABILITIESCVE-2021-33527

CRITICAL

CVE-2021-33527

CWE-20Published: August 2, 2021· Updated: Jun 17, 2026

9.8

CVSS v3.1

Official Description

In MB connect line mbDIALUP versions <= 3.9R0.0 a remote attacker can send a specifically crafted HTTP request to the service running with NT AUTHORITY\SYSTEM that will not correctly validate the input. This can lead to an arbitrary code execution with the privileges of the service.

NVD Source

Technical Analysis

CVE-2021-33527 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.