# CVE-2026-128052: OpenMage magento-lts before 20.19.0 Block Whitelist Bypass via {{layout}} Directive

Status: published. Published: 2026-11-13. Updated: 2026-11-13.

OpenMage magento-lts before 20.19.0 and 21.0.0-beta1 before 21.0.0-beta3 contains an incorrect authorization vulnerability in the template filter's {{layout}} directive, which renders arbitrary layout handles without enforcing the admin/block whitelist that the {{block}} directive applies. Administrators with rights to edit email, CMS, widget or newsletter content can embed {{layout}} with arbitrary handles to render disallowed blocks and disclose limited information.

## 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/OpenMage/magento-lts/commit/055ccb866c0fadfed2c27e8c0e9ebd10db0199df

## Affected products and versions

- OpenMage / magento-lts: ≥ 0; < 20.19.0 (affected, semver); 20.19.0 (unaffected, semver). Source: CNA: VulnCheck
- OpenMage / magento-lts: ≥ 21.0.0-beta1; < 21.0.0-beta3 (affected, semver); 21.0.0-beta3 (unaffected, semver). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 5.1 (medium); CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 2.7 (low); CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N; source: CNA: VulnCheck

- CVSS 4.0: 5.1 (medium); CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:N/VA:N/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: 2.7 (low); CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N; source: NVD: disclosure@vulncheck.com

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-863

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/OpenMage/magento-lts/security/advisories/GHSA-fqq6-76qg-2r96 (CNA: VulnCheck; vendor-advisory)

- https://github.com/OpenMage/magento-lts/commit/055ccb866c0fadfed2c27e8c0e9ebd10db0199df (CNA: VulnCheck; patch)

- https://www.vulncheck.com/advisories/openmage-magento-lts-before-20.19.0-block-whitelist-bypass-via-layout-directive (CNA: VulnCheck; third-party-advisory)

- https://github.com/OpenMage/magento-lts/commit/055ccb866c0fadfed2c27e8c0e9ebd10db0199df (disclosure@vulncheck.com)

- https://github.com/OpenMage/magento-lts/security/advisories/GHSA-fqq6-76qg-2r96 (disclosure@vulncheck.com)

- https://www.vulncheck.com/advisories/openmage-magento-lts-before-20.19.0-block-whitelist-bypass-via-layout-directive (disclosure@vulncheck.com)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-128052; retrieved 2026-11-13; source updated 2026-11-13

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-128052; retrieved 2026-11-13; source updated 2026-11-13

Revision: 6b2879e0a1119a718794fb1b1cd4918beff0cfcbb73f82ca2e7f5c49e1170346

Canonical: https://y2.dev/cve/CVE-2026-128052

## Agent and API access

Public CVE pages, Markdown, and JSON are free to read without an account or API key.

- 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.

Collected public records only. Check source status for coverage and freshness.