CVE REMEDIATION GUIDE
CISA KEV · Known exploitedMediumFixed-version data available

CVE-2018-19953 remediation guide

QNAP Network Attached Storage (NAS)

If exploited, this cross-site scripting vulnerability could allow remote attackers to inject malicious code. QNAP has already fixed the issue in the following QTS versions. QTS 4.4.2.1231 on build 20200302; QTS 4.4.1.1201 on build 20200130; QTS 4.3.6.1218 on build 20200214; QTS 4.3.4.1190 on build 20200107; QTS 4.3.3.1161 on build 20200109; QTS 4.2.6 on build 20200109.

Open CVE record
ProductQNAP Network Attached Storage (NAS)
Affected versionsunspecified, < 4.2.6, >= 4.3.1.0013 < 4.3.3.1161, >= 4.3.4 < 4.3.4.1190, >= 4.3.6 < 4.3.6.1218, >= 4.4.0 < 4.4.1.1201, >= 4.4.2 < 4.4.2.1231, 4.2.6
Fixed versions4.2.6, 4.3.3.1161, 4.3.4.1190, 4.3.6.1218, 4.4.1.1201, 4.4.2.1231
Priority basisImmediate · CVSS 6.1 · EPSS 23.9%
01

Identify the affected asset

Confirm whether QNAP Network Attached Storage (NAS) is installed, record the deployed version and installation path, and identify exposed interfaces.

  • Record the product name, package or appliance identifier, and installed version.
  • Identify internet-facing, administrative, API, and internal access paths.
  • Preserve the pre-change configuration and relevant service logs.
02

Validate the affected-version match

Compare the deployed version with the affected range: unspecified, < 4.2.6, >= 4.3.1.0013 < 4.3.3.1161, >= 4.3.4 < 4.3.4.1190, >= 4.3.6 < 4.3.6.1218, >= 4.4.0 < 4.4.1.1201, >= 4.4.2 < 4.4.2.1231, 4.2.6. Treat incomplete inventory results as unresolved.

03

Prioritize with independent signals

CISA has listed this vulnerability in the Known Exploited Vulnerabilities catalog. Combine this signal with asset criticality, exposure, compensating controls, and business impact.

04

Apply supported remediation

Apply updates per vendor instructions.

05

Verify the result

Confirm the resulting version, service health, authentication and access paths, monitoring coverage, and relevant security logs.

  • Confirm the expected version and package state.
  • Run a functional health check for critical service paths.
  • Review authentication, error, application, and security monitoring logs.
  • Reassess exposure if the supported fix cannot be applied.

Operational boundary

This page does not replace the vendor advisory, support contract, change-management process, or recovery plan. Do not infer that an asset is unaffected from an incomplete inventory query or a missing fixed-version field.