Description
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.
References (4)
Core 4
Core References
Third Party Advisory x_refsource_confirm
https://github.com/mganss/HtmlSanitizer/security/advisories/GHSA-8j9v-h2vp-2hhv
Product, Third Party Advisory x_refsource_misc
https://www.nuget.org/packages/HtmlSanitizer/
Release Notes, Third Party Advisory x_refsource_misc
https://github.com/mganss/HtmlSanitizer/releases/tag/v5.0.372
Patch, Third Party Advisory x_refsource_misc
https://github.com/mganss/HtmlSanitizer/commit/a3a7602a44d4155d51ec0fbbedc2a49e9c7e2eb8
Scores
CVSS v3
6.1
EPSS
0.0034
EPSS Percentile
57.0%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:N/I:H/A:N
Details
CWE
CWE-74
CWE-79
Status
published
Products (2)
htmlsanitizer_project/htmlsanitizer
< 5.0.372
nuget/HtmlSanitizer
0 - 5.0.372NuGet
Published
Jan 04, 2021
Tracked Since
Feb 18, 2026