CVE-2025-66280: CWE-190 in QNAP Systems Inc. QTS
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
AI Analysis
Technical Summary
This vulnerability involves an integer overflow or wraparound in QNAP QTS operating systems. Exploitation requires the attacker to have administrator-level access, after which they can leverage the flaw to compromise the system's security. The vendor has released fixes in 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, and QuTS hero h6.0.0.3397 build 20260206 and later.
Potential Impact
Successful exploitation allows an attacker with administrator privileges to compromise the security of the affected QNAP system. The vulnerability is rated medium severity with a CVSS 4.0 score of 5.1, reflecting a moderate impact on confidentiality, integrity, or availability.
Mitigation Recommendations
The vulnerability has been fixed by QNAP in QTS 5.2.9.3410 build 20260214 and later, and in specified QuTS hero versions. Users should upgrade to these fixed versions to remediate the issue. No additional mitigation steps are indicated by the vendor advisory.
CVE-2025-66280: CWE-190 in QNAP Systems Inc. QTS
Description
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
CVSS v4.0
Score 5.1medium
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves an integer overflow or wraparound in QNAP QTS operating systems. Exploitation requires the attacker to have administrator-level access, after which they can leverage the flaw to compromise the system's security. The vendor has released fixes in 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, and QuTS hero h6.0.0.3397 build 20260206 and later.
Potential Impact
Successful exploitation allows an attacker with administrator privileges to compromise the security of the affected QNAP system. The vulnerability is rated medium severity with a CVSS 4.0 score of 5.1, reflecting a moderate impact on confidentiality, integrity, or availability.
Mitigation Recommendations
The vulnerability has been fixed by QNAP in QTS 5.2.9.3410 build 20260214 and later, and in specified QuTS hero versions. Users should upgrade to these fixed versions to remediate the issue. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- qnap
- Date Reserved
- 2025-11-26T09:25:37.833Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a28dcc28dd33fbd85dba9ba
Added to database: 6/10/2026, 3:40:50 AM
Last enriched: 6/10/2026, 3:56:49 AM
Last updated: 6/10/2026, 2:17:25 PM
Views: 4
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