CVE-2025-66281
High
Description
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
SeverityHigh
CVSS7.2
Exploit probability—
Product
Qnap Quts Hero
PublishedJun 10, 2026
First seenJun 10, 2026
Weakness typeCWE-476NULL pointer dereference
How to fix
Update
- qnap quts_heroh5.2.9.3410, h5.3.4.3500, h6.0.0.3397 or later
- qnap qts5.2.9.3410 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| qnap quts_hero | h5.2.0.2737 ≤ v < h5.2.9.3410, h5.3.0.3115 ≤ v < h5.3.4.3500, h6.0.0.3324 ≤ v < h6.0.0.3397 | h5.2.9.3410, h5.3.4.3500, h6.0.0.3397 |
| qnap qts | 5.2.0.2737 ≤ v < 5.2.9.3410 | 5.2.9.3410 |
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