CVE-2025-66281: QTS, QuTS hero

Published Jun 10, 2026
·
Updated

A NULL pointer dereference vulnerability has been reported to affect several QNAP operating system versions. The remote attackers can then exploit the vulnerability to launch a denial-of-service (DoS) attack.

We have already fixed the vulnerability in the following versions: QTS 5.2.9.3410 build 20260214 and later QuTS hero h5.2.9.3410 build 20260214 and later QuTS hero h5.3.4.3500 build 20260520 and later QuTS hero h6.0.0.3397 build 20260206 and later

Affected Software

6 affected components
QNAP QTS<5.2.9.3410 build 20260214
QNAP QuTS hero<h5.2.9.3410 build 20260214, <h5.3.4.3500 build 20260520, <h6.0.0.3397 build 20260206
QNAP QTS>=5.2.0.2737<5.2.9.3410
QNAP QuTS hero>=h5.2.0.2737<h5.2.9.3410
QNAP QuTS hero>=h5.3.0.3115<h5.3.4.3500
QNAP QuTS hero>=h6.0.0.3324<h6.0.0.3397

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade QTS to a version that resolves this vulnerability.

    Fixed in 5.2.9.3410 build 20260214
  2. Upgrade

    Upgrade QuTS hero to a version that resolves this vulnerability.

    Fixed in h5.2.9.3410 build 20260214
  3. Upgrade

    Upgrade QuTS hero to a version that resolves this vulnerability.

    Fixed in h5.3.4.3500 build 20260520
  4. Upgrade

    Upgrade QuTS hero to a version that resolves this vulnerability.

    Fixed in h6.0.0.3397 build 20260206

Event History

Jun 10, 2026
CVE Published
via MITRE·03:06 AM
Data Sourced
via MITRE·03:06 AM
RemedyDescriptionWeakness
Data Sourced
via NVD·04:17 AM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2025-66281?

CVE-2025-66281 has a medium severity rating of 6.9 according to the CVSS.

2

What is CVE-2025-66281?

CVE-2025-66281 is a NULL pointer dereference vulnerability affecting several versions of QNAP operating systems.

3

How can CVE-2025-66281 be exploited?

Remote attackers can exploit CVE-2025-66281 to launch a denial-of-service (DoS) attack.

4

How do I fix CVE-2025-66281?

To fix CVE-2025-66281, update to QTS version 5.2.9.3410 build 20260214 or later, or the respective QuTS hero versions.

5

Which versions of QNAP software are affected by CVE-2025-66281?

CVS-2025-66281 affects several QNAP operating system versions prior to the specified fixed builds.

Contact

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