Vulnerability · Published Jun 10, 2026 · Assigned by qnap

CVE-2025-66281QTS, QuTS hero

Medium 6.9

In plain English

A medium-severity null pointer dereference 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 0.5% (higher than 40% of all known vulnerabilities).

Severity (CVSS 4.0)6.9Medium
Exploit odds (30 days)0.5%top 60.2% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official 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

Affected products (as reported)

VendorProductVersions
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-476 · Vector: 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

References