CVE-2025-66280
published 2026-06-10CVE-2025-66280: An integer overflow or wraparound vulnerability has been reported to affect several QNAP operating system versions. If a remote attacker gains an administrator…
PriorityP351high7.2CVSS 3.1
AVNACLPRHUINSUCHIHAH
EPSS
0.43%
34.8th percentile
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
8 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| qnap | qts | >= 5.2.0.2737 < 5.2.9.3410 | 5.2.9.3410 |
| qnap | quts_hero | >= h5.2.0.2737 < h5.2.9.3410 | h5.2.9.3410 |
| qnap | quts_hero | >= h5.3.0.3115 < h5.3.4.3500 | h5.3.4.3500 |
| qnap | quts_hero | >= h6.0.0.3324 < h6.0.0.3397 | h6.0.0.3397 |
| qnap_systems_inc | qts | >= 5.2.0 < 5.2.9.3410 build 20260214 | 5.2.9.3410 build 20260214 |
| qnap_systems_inc | quts_hero | >= ? < h6.0.0.3397 build 20260206 | h6.0.0.3397 build 20260206 |
| qnap_systems_inc | quts_hero | >= h5.2.0 < h5.2.9.3410 build 20260214 | h5.2.9.3410 build 20260214 |
| qnap_systems_inc | quts_hero | >= h5.3.0 < h5.3.4.3500 build 20260520 | h5.3.4.3500 build 20260520 |
CVSS provenance
nvdv3.17.2HIGHCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
nvdv4.05.1MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
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VulDB
QNAP QTS/QuTS hero 5.2.9.3410/5.3.4.3500/6.0.0.3397 integer overflow (qsa-26-10 / EUVD-2025-210101)
vuldb·2026-06-16·CVSS 7.2
CVE-2025-66280 [HIGH] QNAP QTS/QuTS hero 5.2.9.3410/5.3.4.3500/6.0.0.3397 integer overflow (qsa-26-10 / EUVD-2025-210101)
A vulnerability marked as problematic has been reported in QNAP QTS and QuTS hero 5.2.9.3410/5.3.4.3500/6.0.0.3397. This affects an unknown function. Performing a manipulation results in integer overflow.
This vulnerability is cataloged as CVE-2025-66280. It is possible to initiate the attack remotely. There is no exploit available.
It is suggested to upgrade the affected component.
GHSA
An integer overflow or wraparound vulnerability has been reported to affect several QNAP operating system versions.
ghsa_unreviewed·2026-06-10
CVE-2025-66280 [MEDIUM] CWE-121 An integer overflow or wraparound vulnerability has been reported to affect several QNAP operating system versions.
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
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-06-10
Published