Semantic MediaWiki affected by Special:Ask table `sep` parameter reflected XSS — GHSA-7XV3-GF2G-498H

Summary

#### Failure mode `sep` was inserted verbatim into the HTML that joins a table cell's values. This made it possible to inject HTML through the separator value. The same unsanitised table HTML is produced both for the standard `Special:Ask` render and for its raw request output (`request_type=raw`), so the injection was reachable without authentication. #### Remediation - In all non-wiki output modes (HTML, raw…

Timeline

Published by source

2026-09-18

Risk context

• Reported severity or threat level: medium.
• Reported CVSS score: 6.1 out of 10.
• Review exposure for the affected product or family: composer: mediawiki/semantic-media-wiki.

Product

composer: mediawiki/semantic-media-wiki

What to do

General, cautious steps (verify details in the official source):

• Review exposure and plan remediation based on risk and environment.
• Identify affected product versions in your inventory and verify whether you are impacted.
• Apply vendor patches/updates or recommended mitigations as soon as available.
• Read the official advisory for exact affected versions and remediation steps.

Official advisory

• Read the official source
• CVE Record
• NVD

Evidence and provenance

Canonical advisory ID

GHSA-7XV3-GF2G-498H

Source

GitHub

Vendor

GitHub

Published by source

2026-09-18

Last source activity

2026-09-18

Additional identifiers

CVE-2026-77607

Curated by

hlukh.ch

Related advisories and connections

These advisories are connected by shared CVE, product, vendor, source, or time signals.