Vulnerability · Published Feb 11, 2026 · Assigned by qnap
CVE-2025-66277QTS, QuTS hero
Critical 9.2
In plain English
A critical-severity security flaw 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 0.7% (higher than 54% of all known vulnerabilities).
Official description
A link following vulnerability has been reported to affect several QNAP operating system versions. The remote attackers can then exploit the vulnerability to traverse the file system to unintended locations. We have already fixed the vulnerability in the following versions: QTS 5.2.8.3350 build 20251216 and later QuTS hero h5.3.2.3354 build 20251225 and later QuTS hero h5.2.8.3350 build 20251216 and later
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| QNAP Systems Inc. | QTS | 5.2.x – before 5.2.8.3350 build 20251216 |
| QNAP Systems Inc. | QuTS hero | h5.3.x – before h5.3.2.3354 build 20251225h5.2.x – before h5.2.8.3350 build 20251216 |
Weakness: CWE-59 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N