Vulnerability · Published Jun 10, 2026 · Assigned by qnap
CVE-2025-66280QTS, QuTS hero
Medium 5.1
In plain English
A medium-severity integer overflow in QTS from QNAP Systems Inc.. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 38% of all known vulnerabilities).
Official description
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 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 products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| QNAP Systems Inc. | QTS | 5.2.0 – before 5.2.9.3410 build 20260214 |
| QNAP Systems Inc. | QuTS hero | h5.2.0 – before h5.2.9.3410 build 20260214h5.3.0 – before h5.3.4.3500 build 20260520? – before h6.0.0.3397 build 20260206 |
Weakness: CWE-190, CWE-121 · Vector: 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