CVE-2020-26293: Htmlsanitizer Project Htmlsanitizer

Medium severity, CVSS 6.1. EPSS: 1% chance of exploitation in the next 30 days.

HtmlSanitizer is a .NET library for cleaning HTML fragments and documents from constructs that can lead to XSS attacks. In HtmlSanitizer before version 5.0.372, there is a possible XSS bypass if style tag is allowed. If you have explicitly allowed the `<style>` tag, an attacker could craft HTML that includes script after passing through the sanitizer. The default settings disallow the `<style>` tag so there is no risk if you have not explicitly allowed the `<style>` tag. The problem has been fixed in version 5.0.372.

Affected products

Published 2021-01-04. Last modified 2026-06-17.