CVE-2026-33979
8.2 · HIGHOverview
CVE-2026-33979 is a high-severity vulnerability affecting express_xss_sanitizer_project express_xss_sanitizer. It was published on March 27, 2026 and has a CVSS 3.1 base score of 8.2 (HIGH).
This vulnerability has a CVSS 3.1 base score of 8.2, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical 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.
Remediation
Check the references section for vendor advisories and patches from express_xss_sanitizer_project. Update express_xss_sanitizer to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| express_xss_sanitizer_project | express_xss_sanitizer | >= 0, < 2.0.2 | Affected |
Frequently Asked Questions
What is CVE-2026-33979?
CVE-2026-33979 is a high-severity vulnerability affecting express_xss_sanitizer_project express_xss_sanitizer. It was published on March 27, 2026 and has a CVSS 3.1 base score of 8.2 (HIGH).
How severe is CVE-2026-33979?
This vulnerability has a CVSS 3.1 base score of 8.2, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-33979?
Check the references section for vendor advisories and patches from express_xss_sanitizer_project. Update express_xss_sanitizer to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-33979?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-33979 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
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