Cyber Resilience

CVE-2025-66280

Medium

Published: 10 June 2026

Published
10 June 2026
Modified
15 June 2026
KEV Added
Patch
CVSS Score v4 5.1 CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:L/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
EPSS Score 0.0033 24.7th percentile
Risk Priority 10 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-66280 is a medium-severity Stack-based Buffer Overflow (CWE-121) vulnerability in Qnap Quts Hero. Its CVSS base score is 5.1 (Medium).

Operationally, ranked at the 24.7th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

An integer overflow or wraparound vulnerability has been reported to affect several QNAP operating system versions. If a remote attacker gains an administrator account, they can then exploit the vulnerability to compromise the security of the system. We have already…

more

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

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

qnap
qts
5.2.0.2737 — 5.2.9.3410
qnap
quts hero
h5.2.0.2737 — h5.2.9.3410 · h5.3.0.3115 — h5.3.4.3500 · h6.0.0.3324 — h6.0.0.3397

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References