CVE-2026-116883
Received Received - Intake

Stored XSS in Semantic MediaWiki Schema Editor

Publication date: 2026-10-27

Last updated on: 2026-10-27

Assigner: VulnCheck

Description
Semantic MediaWiki from 3.1.0 before 7.3.1 contains a stored cross-site scripting vulnerability that allows authenticated schema editors to inject HTML through schema descriptions. Attackers with the smw-schemaedit permission can save HTML that is passed unescaped to Html::rawElement() in HtmlBuilder, altering pages and targeting users who view the schema.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published
2026-10-27
Last Modified
2026-10-27
Generated
2026-10-27
AI Q&A
2026-10-27
EPSS Evaluated
N/A
NVD
CVE-2026-116883
EUVD
EUVD-2026-110711

Affected Vendors & Products

Showing 1 associated CPE
Vendor Product Version / Range
SemanticMediaWiki SemanticMediaWiki 3.1.0

Helpful Resources

Exploitability

CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-79 The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

Attack-Flow Graph

AI Quick Actions

Instant insights powered by AI
Executive Summary

This is a stored cross-site scripting (XSS) vulnerability in Semantic MediaWiki versions 3.1.0 through 7.3.0. Authenticated users with the smw-schemaedit permission can inject malicious HTML into schema descriptions. The HTML is not properly sanitized and is rendered unescaped, potentially altering pages and targeting users who view the affected schema.

Detection Guidance

To detect this vulnerability, check if your Semantic MediaWiki instance is running versions 3.1.0 through 7.3.0. Review schema descriptions for unexpected HTML or script tags. Inspect files like SchemaContentFormatter.php and HtmlBuilder.php for improper HTML rendering without sanitization.

Impact Analysis

The vulnerability allows attackers to inject HTML that can alter pages and target users viewing schemas. While it requires high privileges (schema-editing access), successful exploitation could lead to unauthorized data access, session hijacking, or defacement of wiki pages.

Mitigation Strategies

Upgrade Semantic MediaWiki to version 7.3.1 or later. Apply strict input sanitization for schema descriptions. Escape HTML at the final rendering stage or use a strict allowlist sanitizer if rich text is required.

Chat Assistant

Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-116883. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70

EPSS Chart