CVEvulnerability

CVE-2026-33979

8.2 HIGH Published 2026-03-27 Modified 2026-06-17 Official page ↗
Status
Analyzed
Published
2026-03-27
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.1 ([email protected])
8.2 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N
Weaknesses
CWE-183, CWE-79

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.

Affected configurations

• express xss sanitizer project express xss sanitizer (< 2.0.2)

Related

Weakness · CWE (2)

  • CWE-183 Permissive List of Allowed Inputs weakness
  • CWE-79 Improper Neutralization of Input During Web Page Generation weakness

References