CVE-2025-66274: CWE-476 in QNAP Systems Inc. QTS
CVE-2025-66274 is a NULL pointer dereference vulnerability in QNAP Systems Inc. QTS operating system. It affects several versions and can be exploited by a remote attacker with administrator privileges to cause a denial-of-service (DoS) condition. The vulnerability has been fixed in QTS 5.2.9.3410 build 20260214 and later, as well as in specific QuTS hero versions. The CVSS 4.0 base score is 5.1, indicating a medium severity level.
AI Analysis
Technical Summary
This vulnerability (CVE-2025-66274) involves a NULL pointer dereference in QNAP QTS operating system versions. An attacker who already has administrator access can exploit this flaw to trigger a denial-of-service attack, causing the system to crash or become unresponsive. The vendor has released official fixes in QTS 5.2.9.3410 build 20260214 and later versions, including QuTS hero h5.2.9.3410 build 20260214, h5.3.2.3354 build 20251225, and h6.0.0.3397 build 20260206. No known exploits are reported in the wild at this time.
Potential Impact
Successful exploitation requires administrator privileges and results in a denial-of-service condition by causing a NULL pointer dereference. This disrupts system availability but does not directly lead to privilege escalation or data compromise based on the provided data.
Mitigation Recommendations
The vulnerability has been officially fixed by QNAP in QTS 5.2.9.3410 build 20260214 and later versions, as well as in specified QuTS hero builds. Users should upgrade to these fixed versions to remediate the issue. No additional mitigation steps are indicated by the vendor advisory.
CVE-2025-66274: CWE-476 in QNAP Systems Inc. QTS
Description
CVE-2025-66274 is a NULL pointer dereference vulnerability in QNAP Systems Inc. QTS operating system. It affects several versions and can be exploited by a remote attacker with administrator privileges to cause a denial-of-service (DoS) condition. The vulnerability has been fixed in QTS 5.2.9.3410 build 20260214 and later, as well as in specific QuTS hero versions. The CVSS 4.0 base score is 5.1, indicating a medium severity level.
CVSS v4.0
Score 5.1medium
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2025-66274) involves a NULL pointer dereference in QNAP QTS operating system versions. An attacker who already has administrator access can exploit this flaw to trigger a denial-of-service attack, causing the system to crash or become unresponsive. The vendor has released official fixes in QTS 5.2.9.3410 build 20260214 and later versions, including QuTS hero h5.2.9.3410 build 20260214, h5.3.2.3354 build 20251225, and h6.0.0.3397 build 20260206. No known exploits are reported in the wild at this time.
Potential Impact
Successful exploitation requires administrator privileges and results in a denial-of-service condition by causing a NULL pointer dereference. This disrupts system availability but does not directly lead to privilege escalation or data compromise based on the provided data.
Mitigation Recommendations
The vulnerability has been officially fixed by QNAP in QTS 5.2.9.3410 build 20260214 and later versions, as well as in specified QuTS hero builds. 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
- 2025-11-26T09:25:37.832Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 698c7a214b57a58fa195d0f4
Added to database: 02/11/2026, 12:46:25 UTC
Last enriched: 06/16/2026, 08:50:31 UTC
Last updated: 09/10/2026, 19:36:51 UTC
Views: 140
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