What is CVE-2026-116878?

CVE-2026-116878 is a high-severity vulnerability in Semanticmediawiki, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2026-10-27.

How severe is CVE-2026-116878?

High severity. CVSS v3 base score is 7.5 out of 10.

Resource exhaustion in Semanticmediawiki

CVE-2026-116878

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.

Vulnerability class: DoS (Denial of Service)

Published 2026-10-27 · last modified 2026-10-27.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Semanticmediawiki

Weakness classification (CWE)

CWE-400 — Uncontrolled Resource Consumption

References

github.com/SemanticMediaWiki/SemanticMediaWiki/security/advisories/GHSA-wh64-r5… (vendor-advisory)
github.com/SemanticMediaWiki/SemanticMediaWiki/commit/15ed8489a4ca142ea5417d0c4… (patch)
www.vulncheck.com/advisories/semantic-mediawiki-2.5.0-before-7.3.1-resource-exh… (third-party-advisory)

Frequently asked questions

What is CVE-2026-116878?: CVE-2026-116878 is a high-severity vulnerability in Semanticmediawiki, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2026-10-27.
How severe is CVE-2026-116878?: High severity. CVSS v3 base score is 7.5 out of 10.