CVE intelligence and bounded remediation

CVE-2021-38674 — A cross-site scripting (XSS) vulnerability has been reported to affect QTS, QuTS hero and QuTScloud

Medium CVSS 6.1

A cross-site scripting (XSS) vulnerability has been reported to affect QTS, QuTS hero and QuTScloud. If exploited, this vulnerability allows remote attackers to inject malicious code. We have already fixed this vulnerability in the following versions of QTS, QuTS hero and QuTScloud: QuTS hero h4.5.4.1771 build 20210825 and later QTS 4.5.4.1787 build 20210910 and later QuTScloud c4.5.7.1864 and later

Severity
Medium
CVSS
6.1 (3.1)
Published
2022-01-07
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-79

Affected products

  • qnap / qts
  • qnap / quts_hero
  • qnap / qutscloud

Matched remediation archetype

Cross-site scripting and unsafe browser output

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Trace reflected, stored, and DOM-derived untrusted values into HTML, attributes, URLs, styles, scripts, and client-side template sinks.
  • Identify affected origins, authenticated user roles, sensitive browser capabilities, and where content is shared across tenants.
  • Review framework escaping, rich-text sanitization, legacy templates, and client-side rendering paths.

Remediate safely

  • Use context-aware framework output encoding and safe DOM APIs; keep untrusted data out of executable contexts.
  • Sanitize intentionally supported markup with a maintained allowlist policy and validate URLs and attributes separately.
  • Update affected rendering components and add tests for every output context using inert sentinel markup.

Authoritative sources

Complete CVE record and remediation plan

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