CVE-2025-66274: QNAP Systems QTS · NULL Pointer Dereference
Affects QNAP Systems QTSSource CVE Database V5
Not known to be exploited · CVSS 5.1 Medium : upgrade to 5.2.9.3410 build 20260214 when convenient.
Data as of 26 Oct 2026, 12:55 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 37% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.2.9.3410 build 20260214, h6.0.0.3397 build 20260206, h5.3.2.3354 build 20251225 +1
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 11 Feb 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade QTS to 5.2.9.3410 build 20260214; QuTS hero to h6.0.0.3397 build 20260206, h5.3.2.3354 build 20251225 or h5.2.9.3410 build 20260214.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| QNAP Systems Inc.QTS | Affected
| Fixed in
|
| QNAP Systems Inc.QuTS hero | Affected
| Fixed in
|
AI-suggested
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.
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.