CVE-2026-116538

HtmlSanitizer before 9.2.1039 and 10.0 prereleases before 10.0.1037-beta contains a cross-site scripting vulnerability because SanitizeDom(string) never sanitizes attributes on the html and body wrapper elements. Attackers can supply input with a second body or html tag carrying event handlers like onload, executing script when applications render serialized document or body outer HTML.

CVSS v3 4.7 MEDIUM

4.7^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity HIGH

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
https://github.com/mganss/HtmlSanitizer/blob/v9.2.995/src/HtmlSanitizer/HtmlSanitizer.cs#L456-L465
https://github.com/mganss/HtmlSanitizer/blob/v9.2.995/src/HtmlSanitizer/HtmlSanitizer.cs#L555-L583
https://github.com/mganss/HtmlSanitizer/commit/96afbc818e64de7571ea17954a05d523e819c56f
https://github.com/mganss/HtmlSanitizer/commit/ab626e7a4f2893f7e9ec0a72779ae19c5ec439a7
https://github.com/mganss/HtmlSanitizer/releases/tag/v10.0.1037-beta
https://github.com/mganss/HtmlSanitizer/releases/tag/v9.2.1039
https://joshua.hu/htmlsanitizer-sanitizedom-body-html-attribute-bypass
https://www.vulncheck.com/advisories/htmlsanitizer-before-9.2.1039-xss-via-sanitizedom-body-and-html-attributes

Configurations

No configuration.

History

26 Oct 2026, 16:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-26 16:17

Updated : 2026-10-31 02:17

NVD link : CVE-2026-116538

Mitre link : CVE-2026-116538

CVE.ORG link : CVE-2026-116538

JSON object : View

Products Affected

No product.

CWE

CWE-79

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

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