Semantic MediaWiki has a query debug output XSS (`DebugFormatter`) (CVE-2026-77610) | HOL Guard CVE

Medium · CVSS 6.1CVE-2026-77610GHSA-Q5FM-9MX6-44F4

Semantic MediaWiki has a query debug output XSS (`DebugFormatter`)

Answer in brief

CVE-2026-77610 records a Medium severity (CVSS 6.1) vulnerability in Semantic MediaWiki has a query debug output XSS (`DebugFormatter`). The current sources do not mark it as known exploited. The current feed maps mediawiki/semantic-media-wiki (composer), SemanticMediaWiki/SemanticMediaWiki (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 18, 2026Updated Sep 18, 2026Source checked Sep 18, 2026First seen by HOL Sep 18, 2026Material review Sep 18, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 6.1
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 6.1. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps mediawiki/semantic-media-wiki (composer), SemanticMediaWiki/SemanticMediaWiki (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
mediawiki/semantic-media-wikicomposer	<=7.1.0	7.2.0
SemanticMediaWiki/SemanticMediaWikigeneric	< 7.2.0	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for mediawiki/semantic-media-wiki, SemanticMediaWiki/SemanticMediaWiki.
Review the reported fix. Update mediawiki/semantic-media-wiki to 7.2.0 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 18, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 18, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 18, 2026

Sources and claim methodology

Upstream source description

Semantic MediaWiki is a free, open-source extension to MediaWiki that lets users store and query data within the wiki's pages. Prior to version 7.2.0, query debug output (`format=debug`, or the `debug` request parameter on `Special:Ask`) is assembled by `SMW\Query\DebugFormatter` and emitted as raw HTML. Several of its sinks apply no output-context encoding, so attacker-controlled query input is reflected into the page without escaping. On `Special:Ask` the resulting string is concatenated into the page and sent through `OutputPage::addHTML`, never through the MediaWiki parser or Sanitizer. No special user right is required; an anonymous request suffices. This is a reflected XSS: the payload is taken from the request and echoed in the same response. Exploitation requires the query condition to target a text/blob-typed property (whose value is re-serialized verbatim); the predefined `_txt` properties (`Text`, etc.) that ship on every install satisfy this, so no attacker-created content is needed. Version 7.2.0 patches the issue.

Quoted source text, attributed separately from HOL analysis.