CVE intelligence and bounded remediation

CVE-2026-21855 — The Tarkov Data Manager is a tool to manage the Tarkov item data

Critical CVSS 9.3

The Tarkov Data Manager is a tool to manage the Tarkov item data. Prior to 02 January 2025, a reflected Cross Site Scripting (XSS) vulnerability in the toast notification system allows any attacker to execute arbitrary JavaScript in the context of a victim's browser session by crafting a malicious URL. A series of fix commits on 02 January 2025 fixed this and other vulnerabilities.

Severity
Critical
CVSS
9.3 (3.1)
Published
2026-01-07
CISA KEV
Not currently listed
Ecosystem
javascript/npm
Weaknesses
CWE-79

Affected products

  • tarkov / tarkov_data_manager

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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