CVE-2026-126563

Description

Semantic MediaWiki 2.4.0 before 7.4.1 contains a reflected cross-site scripting vulnerability in TimeValueFormatter::getCaptionFromFreeFormat(), which emits free-format date captions in HTML without escaping. Unauthenticated attackers can craft a Special:Ask URL with HTML markup in a date printout format (#-F[...]) to execute script in a logged-in victim's browser session.

References

• https://github.com/SemanticMediaWiki/SemanticMediaWiki/blob/7.4.0/src/DataValues/ValueFormatters/TimeValueFormatter.php#L312-L340
• https://github.com/SemanticMediaWiki/SemanticMediaWiki/commit/01cb81a6da7af743d2a5eb334db10e52b7318c56
• https://github.com/SemanticMediaWiki/SemanticMediaWiki/releases/tag/7.4.1
• https://github.com/SemanticMediaWiki/SemanticMediaWiki/security/advisories/GHSA-h252-mj7p-58q7
• https://www.vulncheck.com/advisories/semantic-mediawiki-2.4.0-before-7.4.1-reflected-xss-via-special-ask-date-format