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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-25543 Detail

Description

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  GitHub, Inc.
CVSS-B 6.3 MEDIUM
Vector:  CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/mganss/HtmlSanitizer/commit/0ac53dca30ddad963f2b243669a5066933d82b81 GitHub, Inc.
https://github.com/mganss/HtmlSanitizer/security/advisories/GHSA-j92c-7v7g-gj3f GitHub, Inc.
https://www.nuget.org/packages/HtmlSanitizer/9.0.892 GitHub, Inc.
https://www.nuget.org/packages/HtmlSanitizer/9.1.893-beta GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-116 Improper Encoding or Escaping of Output GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-25543
NVD Published Date:
02/04/2026
NVD Last Modified:
02/05/2026
Source:
GitHub, Inc.