CVE record · CVE-2025-66277

QTS, QuTS hero

CVSS 9.2 CriticalCriticalEPSS 0.0071 · 53rd percentile

Critical, because:

CVSS score 9.2: 9.0 or more.

Published by the CVE Program (CNA: qnap) at 11 Feb 2026, 12:15 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. This CVE names a vendor and product rather than a package, so the lockfile check doesn’t match it.

Affected products, as the CNA wrote them
Vendor	Product	Versions
QNAP Systems Inc.	QTS	affected 5.2.x to before 5.2.8.3350 build 20251216 custom Other versions: unaffected
QNAP Systems Inc.	QuTS hero	affected h5.3.x to before h5.3.2.3354 build 20251225 custom affected h5.2.x to before h5.2.8.3350 build 20251216 custom Other versions: unaffected

Identifiers: CVE-2025-66277
CNA: qnap
Weakness (CWE): CWE-59
Tags: QNAP Systems Inc. QTS
QNAP Systems Inc. QuTS hero
Path traversal
Published: 11 Feb 2026
Updated: 26 Feb 2026

Not analysed yet

We haven’t published our own analysis of this CVE. If a person reviews it, this page will say what’s affected and what has to be true for it to matter.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
9.2	Critical	4.0	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	CNA (qnap)

CISA KEV Not listed.
EPSS 0.0071, the 53rd percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

This record came from the full history of the CVE Program, published 11 Feb 2026. New records show when each source confirmed them.

Sources

References from the CNA

www.qnap.com/en/security-advisory/qsa-26-05

Facts on this page come from the CVE List as the CNA published them, with CVSS from the sources named above, CISA KEV and FIRST EPSS. Vendors, products and versions are shown as the CNA wrote them. We don’t reproduce the CVE’s description.