CVE intelligence and bounded remediation
CVE-2026-37503 — Cross-Site Scripting (XSS) in V2Board thru 1.7.4
Medium
CVSS 6.9
Cross-Site Scripting (XSS) in V2Board thru 1.7.4. The custom_html field in theme configuration is rendered using Blade unescaped output in public/theme/v2board/dashboard.blade.php. An admin can inject arbitrary JavaScript via the saveThemeConfig API. All site visitors execute the payload, enabling cookie theft, session hijacking, or phishing.
- Severity
- Medium
- CVSS
- 6.9 (3.1)
- Published
- 2026-05-01
- CISA KEV
- Not currently listed
- Ecosystem
- javascript/npm
- Weaknesses
- CWE-79
Affected products
- v2board / v2board
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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