Out-of-bounds Read in QNAP Qts

CVE-2025-54166

An out-of-bounds read 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 obtain secret data. We have already fixed the vulnerability in the following versions: QTS 5.2.7.3256 build 20250913 and later QuTS hero h5.2.7.3256 build 20250913 and later QuTS hero h5.3.1.3250 build 20250912 and later

Vulnerability class: Buffer Overflow

EPSS: 0.003 (20.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.9 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-54166?
CVE-2025-54166 is a medium-severity vulnerability in QNAP Qts, classified under Out-of-bounds Read. CVSS score: 4.9/10. Published 2026-01-02.
How severe is CVE-2025-54166?
Medium severity. CVSS v3 base score is 4.9 out of 10.