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CVE Record

CVE-2025-66276: QTS

QuTS hero is not affected. We have already fixed the vulnerability in the following version: QTS 5.2.7.3256 build 20250913 and later

CriticalCVSS 9.2Not KEV-listedUpdated
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Glexia's TakeAutomated analysiscritical

Security readout for executives and security teams

Plain-English summary

QNAP reports a critical vulnerability in QTS, with QuTS hero explicitly not affected. The issue is fixed in QTS 5.2.7.3256 build 20250913 and later. The source bundle does not describe the bug class, so prioritize version exposure and vendor guidance rather than assuming a specific attack path.

Executive priority

Prioritize this for rapid remediation on QNAP QTS systems, especially business-critical storage. The available facts show critical potential impact and a vendor-fixed version, but no supplied evidence of active exploitation.

Technical view

The CVSS 4.0 score is 9.2: network attack vector, low complexity, no privileges, no user interaction, and high impact to confidentiality, integrity, and availability. The vector includes attack requirements present, but the advisory details supplied do not explain those prerequisites or the vulnerability mechanism.

Likely exposure

Exposure appears limited to QNAP QTS, with QTS 5.2.0 listed in the source bundle and fixed builds starting at 5.2.7.3256 build 20250913. QuTS hero is listed as unaffected. Confirm exact affected build scope against QNAP’s advisory before broad remediation assumptions.

Exploitation context

The bundle does not provide evidence of active exploitation, and KEV is false. Treat this as high urgency because of critical severity and network-reachable impact, but do not claim exploitation in the wild based on the supplied evidence.

Researcher notes

The public details in the bundle are sparse: no CWE, root cause, endpoint, or exploit preconditions beyond the CVSS vector. Validation should focus on asset/build matching and monitoring for QNAP advisory updates, not speculative vulnerability testing.

Mitigation direction

  • Upgrade QTS to 5.2.7.3256 build 20250913 or later.
  • Verify QuTS hero assets separately; QNAP says they are not affected.
  • Check QNAP advisory QSA-25-56 for any updated guidance.
  • Limit network exposure of QNAP management interfaces where operationally feasible.

Validation and detection

  • Inventory QNAP NAS assets and record product, firmware, and build numbers.
  • Flag QTS 5.2.0 and builds older than 5.2.7.3256 for remediation review.
  • Confirm upgraded devices report QTS 5.2.7.3256 build 20250913 or later.
  • Document QuTS hero systems as not affected per QNAP, pending advisory changes.
Prepared
Confidence
medium
Sources
3

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

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CVE-2025-66276 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

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Vulnerability profileCVE Program record
Severity
Critical
CVSS
9.2 (4.0)
Known Exploited
No
Published

Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

1CVSS vectors
3Timeline events
1ADP providers
2Source links

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: noneAutomatable: noTechnical Impact: total

CVSS vector scores

1 official score

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
9.2CVSS 4.0CriticalCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N——qnap

Vulnerability scoring details

Base CVSS 4.0 score

9.2Critical
CVSS 4.0 vector shape for CVE-2025-66276Attack VectorAttack ComplexityAttack RequirementsPrivileges RequiredUser InteractionVS ConfidentialityVS IntegrityVS AvailabilitySS ConfidentialitySS IntegritySS Availability

Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Attack Requirements
NonePresent
Privileges Required
NoneLowHigh
User Interaction
NonePassiveActive
VS Confidentiality
HighLowNone
VS Integrity
HighLowNone
VS Availability
HighLowNone
SS Confidentiality
HighLowNone
SS Integrity
HighLowNone
SS Availability
HighLowNone

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. CVE publishedCVE Program

    The CVE record was published.

  3. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

CISA-ADPCISA ADP Vulnrichment
other:ssvc

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
QNAP Systems Inc.QTS5.2.0unaffected
QNAP Systems Inc.QuTS hero?unaffected
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.