GHSA-q5fm-9mx6-44f4 — mediawiki/semantic-media-…
MEDIUMGHSA-q5fm-9mx6-44f4 is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in mediawiki/semantic-media-wiki. A fix is available for mediawiki/semantic-media-wiki — see the affected versions and patch details below.
Semantic MediaWiki has a query debug output XSS (`DebugFormatter`)
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-q5fm-9mx6-44f4 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,166 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
mediawiki/semantic-media-wikiReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
Query debug output XSS
Failure mode
Semantic MediaWiki's 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:
buildHTML()echoes the re-serialized ASK query string escaping only[;<,>,",'pass through.prettifySQL()returns the generated SQL verbatim. Query value literals are inlined into the SQL through the database layer's quoting (SQL-escaping only, no HTML encoding), so markup in a value survives.prettifyExplain()echoesEXPLAINoutput; on PostgreSQL the plan text contains theWHEREliterals.
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. Example request:
Special:Ask?q=[[Text::<script>alert(document.domain)</script>]]&debug=1
Remediation
- Apply output-context escaping at the
DebugFormatterboundary. ThebuildHTML()contract already assumes its inputs are HTML-safe, but its callers do not honour that; escape each entry value on emission, and the SQL andEXPLAINstrings before they are wrapped. - Escaping only the query-string echo is insufficient:
prettifySQL()and the "Auxilliary Tables" executed-query text carry the same attacker-controlled literals.
Scope
The prettifySPARQL() sink already encodes < and > and is not affected. The same debug path is also reachable through inline {{#ask:...|format=debug}}, but that output returns into parser context and is sanitized there; the reflected Special:Ask path is the exposed sink.
Relationship to GHSA-5jhc-3j2f-52rv
This issue was identified while splitting the consolidated report GHSA-5jhc-3j2f-52rv into per-vulnerability advisories. It is distinct from the four items in that report (plain table header, sep, SearchByProperty value, open redirect) and from Special:Ask form-input XSS (which is escaped separately).
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | mediawiki/semantic-media-wiki | all versions | 7.2.0composer require mediawiki/semantic-media-wiki:^7.2.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for mediawiki/semantic-media-wiki, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update mediawiki/semantic-media-wiki to 7.2.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-q5fm-9mx6-44f4 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-q5fm-9mx6-44f4 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-q5fm-9mx6-44f4. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-q5fm-9mx6-44f4 in your dependencies?
O3 Security finds GHSA-q5fm-9mx6-44f4 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.