CVE-2026-33979
Description
Express XSS Sanitizer is Express 4.x and 5.x middleware which sanitizes user input data (in req.body, req.query, req.headers and req.params) to prevent Cross Site Scripting (XSS) attack. A vulnerability has been identified in versions prior to 2.0.2 where restrictive sanitization configurations are silently ignored. In version 2.0.2, the validation logic has been updated to respect explicitly provided empty configurations. Now, if allowedTags or allowedAttributes are provided (even if empty), they are passed directly to sanitize-html without being overridden.
How to fix
- express_xss_sanitizer_project express_xss_sanitizer2.0.2 or later
- express-xss-sanitizer2.0.2 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| express_xss_sanitizer_project express_xss_sanitizer | v < 2.0.2 | 2.0.2 |
| express-xss-sanitizernpm | v < 2.0.2 | 2.0.2 |
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Attack Surface Management
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