CVE-2026-116878

Description

Semantic MediaWiki from 2.5.0 before 7.3.1 contains an uncontrolled resource consumption vulnerability that allows anonymous attackers to force quadratic computation by supplying a zero limit to Special:PropertyLabelSimilarity. Attackers can send repeated requests with limit=0 to bypass the SQL LIMIT and trigger pairwise similar_text() comparisons, exhausting PHP CPU, memory, and database connections.

References

• https://github.com/SemanticMediaWiki/SemanticMediaWiki/commit/15ed8489a4ca142ea5417d0c4403dbbe0a3ee3f5
• https://github.com/SemanticMediaWiki/SemanticMediaWiki/security/advisories/GHSA-wh64-r5x2-vjgf
• https://www.vulncheck.com/advisories/semantic-mediawiki-2.5.0-before-7.3.1-resource-exhaustion-via-special-propertylabelsimilarity