# CVE-2026-126562: Semantic MediaWiki 3.0.0 before 7.4.1 Uncontrolled Recursion via ElasticStore ConceptDescriptionInterpreter

Status: published. Published: 2026-11-11. Updated: 2026-11-14.

Semantic MediaWiki 3.0.0 before 7.4.1 contains an uncontrolled recursion vulnerability in the ElasticStore ConceptDescriptionInterpreter that only detects directly self-referencing concepts. Users with page-edit rights can create mutually referencing concept pages, causing concept page views, Special:Ask, or api.php action=ask queries to exhaust PHP memory or stack.

## Remediation

- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: VulnCheck) — https://github.com/SemanticMediaWiki/SemanticMediaWiki/commit/35d8f8c9c7b48a476751ca0b795b78b648756828

## Affected products and versions

- SemanticMediaWiki / SemanticMediaWiki (mediawiki/semantic-media-wiki): ≥ 3.0.0; < 7.4.1 (affected, semver); 7.4.1 (unaffected, semver). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 5.3 (medium); CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 4.3 (medium); CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L; source: CNA: VulnCheck

- CVSS 4.0: 5.3 (medium); CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X; source: NVD: disclosure@vulncheck.com

- CVSS 3.1: 4.3 (medium); CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L; source: NVD: disclosure@vulncheck.com

- CISA KEV: No listing in collected sources

- EPSS: 0.35% as of 2026-11-13; percentile 29.11%

- SSVC: exploitation poc; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-674

## Exploit evidence

- exploit: https://github.com/SemanticMediaWiki/SemanticMediaWiki/security/advisories/GHSA-jwx8-mm92-gv95 (ADP: CISA-ADP)

## References

- https://github.com/SemanticMediaWiki/SemanticMediaWiki/security/advisories/GHSA-jwx8-mm92-gv95 (CNA: VulnCheck; vendor-advisory)

- https://github.com/SemanticMediaWiki/SemanticMediaWiki/commit/35d8f8c9c7b48a476751ca0b795b78b648756828 (CNA: VulnCheck; patch)

- https://github.com/SemanticMediaWiki/SemanticMediaWiki/releases/tag/7.4.1 (CNA: VulnCheck; release-notes)

- https://github.com/SemanticMediaWiki/SemanticMediaWiki/blob/7.4.0/src/Elastic/QueryEngine/DescriptionInterpreters/ConceptDescriptionInterpreter.php#L34-L75 (CNA: VulnCheck; technical-description)

- https://www.vulncheck.com/advisories/semantic-mediawiki-3.0.0-before-7.4.1-uncontrolled-recursion-via-elasticstore-conceptdescriptioninterpreter (CNA: VulnCheck; third-party-advisory)

- https://github.com/SemanticMediaWiki/SemanticMediaWiki/security/advisories/GHSA-jwx8-mm92-gv95 (ADP: CISA-ADP; exploit)

- https://github.com/SemanticMediaWiki/SemanticMediaWiki/blob/7.4.0/src/Elastic/QueryEngine/DescriptionInterpreters/ConceptDescriptionInterpreter.php#L34-L75 (disclosure@vulncheck.com)

- https://github.com/SemanticMediaWiki/SemanticMediaWiki/commit/35d8f8c9c7b48a476751ca0b795b78b648756828 (disclosure@vulncheck.com)

- https://github.com/SemanticMediaWiki/SemanticMediaWiki/releases/tag/7.4.1 (disclosure@vulncheck.com)

- https://github.com/SemanticMediaWiki/SemanticMediaWiki/security/advisories/GHSA-jwx8-mm92-gv95 (disclosure@vulncheck.com)

- https://www.vulncheck.com/advisories/semantic-mediawiki-3.0.0-before-7.4.1-uncontrolled-recursion-via-elasticstore-conceptdescriptioninterpreter (disclosure@vulncheck.com)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-126562; retrieved 2026-11-14; source updated 2026-11-14

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-126562; retrieved 2026-11-13; source updated 2026-11-12

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-126562; retrieved 2026-11-14; source updated Not reported

Revision: 72e18ee89767a4270138920666b070bcf77f2e60a2fb59db46ac10bb04bf4010

Canonical: https://y2.dev/cve/CVE-2026-126562

## Agent and API access

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- Public catalog: https://y2.dev/cve/index.json. Follow nextCursor with the same search, filters, sort, and limit (1–100). A null cursor marks the end.

- WebMCP: search_cve_disclosures, get_cve_disclosure, get_cve_page_markdown, get_y2_cve_access. Available in compatible browsers.

- Cyber API: https://api.y2.dev/api/v2/cyber/cves and https://api.y2.dev/api/v2/cyber/cves/{cveId}.

- Y2 Pro or Elite: create a workspace API key with the intel:cyber scope and send Authorization: Bearer <Y2_API_KEY>. Setup: https://y2.dev/docs/api/create-key.

- x402: Pay per request without an account or API key. Omit Authorization, read the HTTP 402 PAYMENT-REQUIRED challenge, validate its current requirements, and retry with PAYMENT-SIGNATURE through an authorized payment client. These browser tools never make payments. Guide: https://y2.dev/docs/api/x402.

- OpenAPI: https://y2.dev/api/openapi.yaml. Agent access metadata: https://y2.dev/cve/agent.json.

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