Vulnerability · Published Sep 18, 2026 · Assigned by GitHub_M
CVE-2026-77610Semantic MediaWiki has a query debug output XSS (`DebugFormatter`)
Medium 6.1
In plain English
A medium-severity cross-site scripting in SemanticMediaWiki from SemanticMediaWiki. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 21% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Packagist | mediawiki/semantic-media-wiki | 7.2.0 | GHSA-q5fm-9mx6-44f4 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| SemanticMediaWiki | SemanticMediaWiki | < 7.2.0 |
Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N