CVE intelligence and bounded remediation

CVE-2026-48559 — Lightweight Music Server (LMS) though security vulnerability

Medium CVSS 5.4

Lightweight Music Server (LMS) though 3.76.0 contains a stored cross-site scripting vulnerability that allows attackers to execute arbitrary JavaScript by embedding malicious HTML in media file metadata tags such as GENRE, ARTIST, or ALBUM. Attackers can introduce a crafted media file into the victim's library, causing the payload to be saved during library scanning and executed automatically in the web interface due to tag content being rendered using Wt::TextFormat::UnsafeXHTML without sanitization in src/lms/ui/Utils.cpp.

Severity
Medium
CVSS
5.4 (3.1)
Published
2026-06-01
CISA KEV
Not currently listed
Ecosystem
javascript/npm
Weaknesses
CWE-79

Affected products

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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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