CVE-2026-39997

Status: Awaiting AnalysisHigh (8.9)—

Severity8.9High · CVSS 4.0

Exploitation probability0.24 %higher than 14% of CVEs

Active exploitationNonot in the CISA catalog

Public exploitNot knownno public code found

A missing authentication for critical function vulnerability has been reported to affect HybridDesk Station. If exploited, the vulnerability could allow remote attackers to gain access to the system.

We have already fixed the vulnerability in the following version: HybridDesk Station 4.2.22 and later

CVSS

Base score: 8.9
Version: 4.0
Vector: CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.24 %
Percentile among all scored CVEs: 14
Score date: 10/20/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1203 Exploitation for Client Executionexecution60 %
Primary impactT1078 Valid Accountsstealth · persistence · privilege escalation · initial access55 %

Inferred by deterministic rules from the CVSS vector and CWE. Indicative only.

ATT&CK mitigations that cover these techniques

Application Developer Guidance Active Directory Configuration User Training User Account Management Privileged Account Management Password Policies

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Qnap — Hybriddesk Station^AI

CWEs

CWE-306

References

Show 1 references

https://www.qnap.com/en/app-release-notes?keyword=HybridDesk%20Station&app=HD_Station&product-line=nas

Raw JSON (NVD)

Show

{
  "id": "CVE-2026-39997",
  "cveTags": [],
  "metrics": {
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        "ssvcData": {
          "id": "CVE-2026-39997",
          "role": "CISA Coordinator",
          "options": [
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              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
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          "version": "2.0.3",
          "timestamp": "2026-10-15T13:31:32.504365Z"
        }
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    "cvssMetricV40": [
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          "Automatable": "NOT_DEFINED",
          "attackVector": "ADJACENT",
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          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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",
          "exploitMaturity": "NOT_DEFINED",
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          "attackComplexity": "LOW",
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          "privilegesRequired": "NONE",
          "subIntegrityImpact": "HIGH",
          "vulnIntegrityImpact": "HIGH",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
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          "vulnAvailabilityImpact": "HIGH",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "subConfidentialityImpact": "HIGH",
          "vulnConfidentialityImpact": "HIGH",
          "confidentialityRequirement": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
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          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED"
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  "affected": [
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      "source": "security@qnapsecurity.com.tw",
      "affectedData": [
        {
          "vendor": "QNAP Systems Inc.",
          "product": "HybridDesk Station",
          "versions": [
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              "version": "4.2.x",
              "lessThan": "4.2.22",
              "versionType": "custom"
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  "published": "2026-10-15T10:17:14.197",
  "references": [
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      "url": "https://www.qnap.com/en/app-release-notes?keyword=HybridDesk%20Station&app=HD_Station&product-line=nas",
      "source": "security@qnapsecurity.com.tw"
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  ],
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      "value": "A missing authentication for critical function vulnerability has been reported to affect HybridDesk Station. If exploited, the vulnerability could allow remote attackers to gain access to the system.\n\nWe have already fixed the vulnerability in the following version:\nHybridDesk Station 4.2.22 and later"
    }
  ],
  "lastModified": "2026-10-15T16:32:39.893",
  "sourceIdentifier": "security@qnapsecurity.com.tw"
}