CVE-2025-66281

published 2026-06-10

CVE-2025-66281: A NULL pointer dereference vulnerability has been reported to affect several QNAP operating system versions. The remote attackers can then exploit the…

Priority P3 45 high 7.2 CVSS 3.1

AV N AC L PR H UI N S U C H I H A H

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

8 ranges

Vendor	Product	Version range	Fixed in
qnap	qts	>= 5.2.0.2737 < 5.2.9.3410	5.2.9.3410
qnap	quts_hero	>= h5.2.0.2737 < h5.2.9.3410	h5.2.9.3410
qnap	quts_hero	>= h5.3.0.3115 < h5.3.4.3500	h5.3.4.3500
qnap	quts_hero	>= h6.0.0.3324 < h6.0.0.3397	h6.0.0.3397
qnap_systems_inc	qts	>= 5.2.0 < 5.2.9.3410 build 20260214	5.2.9.3410 build 20260214
qnap_systems_inc	quts_hero	>= ? < h6.0.0.3397 build 20260206	h6.0.0.3397 build 20260206
qnap_systems_inc	quts_hero	>= h5.2.0 < h5.2.9.3410 build 20260214	h5.2.9.3410 build 20260214
qnap_systems_inc	quts_hero	>= h5.3.0 < h5.3.4.3500 build 20260520	h5.3.4.3500 build 20260520

CVSS provenance

nvd v3.1 7.2 HIGH CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

nvd v4.0 6.9 MEDIUM CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

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