CVE-2026-25543

HtmlSanitizer is a .NET library for cleaning HTML fragments and documents from constructs that can lead to XSS attacks. Prior to versions 9.0.892 and 9.1.893-beta, if the template tag is allowed, its contents are not sanitized. The template tag is a special tag that does not usually render its contents, unless the shadowrootmode attribute is set to open or closed. This issue has been patched in versions 9.0.892 and 9.1.893-beta.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/mganss/HtmlSanitizer/commit/0ac53dca30ddad963f2b243669a5066933d82b81	Patch
https://github.com/mganss/HtmlSanitizer/security/advisories/GHSA-j92c-7v7g-gj3f	Mitigation Patch Vendor Advisory
https://www.nuget.org/packages/HtmlSanitizer/9.0.892	Product Release Notes
https://www.nuget.org/packages/HtmlSanitizer/9.1.893-beta	Product Release Notes

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:htmlsanitizer_project:htmlsanitizer::::::::
	cpe:2.3:a:htmlsanitizer_project:htmlsanitizer::::::::

History

No history.

Information

Published : 2026-02-04 22:16

Updated : 2026-02-24 21:29

NVD link : CVE-2026-25543

Mitre link : CVE-2026-25543

CVE.ORG link : CVE-2026-25543

JSON object : View

Products Affected

htmlsanitizer_project

htmlsanitizer

CWE

CWE-116

Improper Encoding or Escaping of Output

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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