QtsOperating system · Qnap

CVE-2020-36194

MEDIUM · 6.1 CVSS v3.1 Published 2021-07-01
Fix available
A fix is available. Upgrade to 4.5.2.1566 or later.
See remediation →
68/100
Remediation priority · Elevated
Remotely reachable No privileges

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
An XSS vulnerability has been reported to affect QNAP NAS running QTS and QuTS hero. If exploited, this vulnerability allows attackers to inject malicious code. This issue affects: QNAP Systems Inc. QTS versions prior to 4.5.2.1566 Build 20210202. QNAP Systems Inc. QuTS hero versions prior to h4.5.2.1638 build 20210414. This issue does not affect: QNAP Systems Inc. QTS 4.5.3.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

A Cross-Site Scripting (XSS) vulnerability in QNAP NAS web interface allows authenticated or unauthenticated attackers to inject malicious JavaScript code via unsanitized input parameters. The vulnerability exists in QTS and QuTS hero firmware versions prior to the specified patch dates, enabling session hijacking, credential theft, or phishing attacks against users accessing the NAS management console.

MitigationApply the vendor-supplied firmware updates: upgrade QTS to version 4.5.2.1566 Build 20210202 or later (or 4.5.3+), and QuTS hero to version h4.5.2.1638 Build 20210414 or later. If immediate patching is not possible, restrict administrative interface access to trusted networks or VPN.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
QtsOperating system
Affected:< 4.5.2.1566
Quts HeroOperating system
Affected:< h4.5.2.1638

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify QNAP NAS device on the network
    Scan network for devices responding on typical QNAP web ports (8080 for HTTP, 443 for HTTPS), or use QNAP Qfinder Pro utility to locate NAS devices
    Affected if A QNAP device is found with its web management interface accessible over the network
  2. Access the firmware version information
    Login to the QTS or QuTS Hero web interface, then navigate to Control Panel > System > Firmware > Firmware Update, or access the API endpoint at /cgi-bin/authLogin.cgi to retrieve system info including firmware version
    Affected if Device is running QTS version prior to 4.5.2.1566 or QuTS Hero version prior to h4.5.2.1638
  3. Verify web administration interface is enabled
    Confirm the NAS web server is running by accessing the login page via HTTP on port 8080 or HTTPS on port 443
    Affected if The web management interface is accessible (the XSS vulnerability exists in this component)
  4. Check if remote access is permitted
    Review network configuration in Control Panel > System > Network > TCP/IP to determine if the admin interface is bound to WAN/external interfaces or only LAN
    Affected if The web interface is exposed beyond the local network (increases exposure risk for unauthenticated exploitation)

A QNAP NAS is affected if its web interface is accessible and the firmware version is below 4.5.2.1566 (QTS) or below h4.5.2.1638 (QuTS Hero).

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Upgrade available Upgrade to 4.5.2.1566 or later
Fixed in 4.5.2.1566
Interim mitigation

Apply the vendor-supplied firmware updates: upgrade QTS to version 4.5.2.1566 Build 20210202 or later (or 4.5.3+), and QuTS hero to version h4.5.2.1638 Build 20210414 or later. If immediate patching is not possible, restrict administrative interface access to trusted networks or VPN.

Fix this in Qts Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
7.0 hours of engineering $1,240
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Scan for this in your stack

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dbcve dependency scanner

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2020-36194 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data