CVE-2026-116878

high

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://www.vulncheck.com/advisories/semantic-mediawiki-2.5.0-before-7.3.1-resource-exhaustion-via-special-propertylabelsimilarity

https://github.com/SemanticMediaWiki/SemanticMediaWiki/security/advisories/GHSA-wh64-r5x2-vjgf

https://github.com/SemanticMediaWiki/SemanticMediaWiki/commit/15ed8489a4ca142ea5417d0c4403dbbe0a3ee3f5

Details

Source: Mitre, NVD

Published: 2026-10-27

Updated: 2026-10-27

Risk Information

CVSS v2

Base Score: 7.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C

Severity: High

CVSS v3

Base Score: 7.5

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Severity: High

CVSS v4

Base Score: 8.7

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Severity: High