Vulnerability in typo3/cms-core (CVE-2026-19418)
Summary
Vulnerability in typo3/cms-core (CVE-2026-19418). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 14.3.6 or later.
Original description
The description as published by the source.
The referrer enforcement introduced with TYPO3-CORE-SA-2020-006 (CVE-2020-11069) became ineffective in TYPO3 v13.0, where TYPO3 CMS started serving the backend and Install Tool applications from the site's main entry script instead of the dedicated typo3/ directory.
Whether a request originated from the backend or Install Tool itself was determined by comparing the referrer against the directory of the entry script, which since then is the site root. As a consequence, requests originating from any script running on one of the TYPO3 instance's own domains, such as a frontend page, were accepted by backend routes and Install Tool endpoints.
Attackers able to execute JavaScript on one of those domains, for instance by exploiting a cross-site scripting vulnerability, could invoke these endpoints via Fetch/XHR with the privileges of an authenticated victim's user session. This issue affects TYPO3 CMS versions 13.0.0-13.4.33 and 14.0.0-14.3.5.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-19418 has been found in typo3/cms-core.
Risk of unauthorized operations or information disclosure.
What to do: upgrade typo3/cms-core to 14.3.6 or later.
If unsure, ask your IT team or search "typo3/cms-core CVE-2026-19418" on the vendor's site.
CVE-2026-19418 (typo3/cms-core) — CWE-346
Patched: 14.3.6 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-346) exists in typo3/cms-core.
Check the vendor advisory for the affected versions of typo3/cms-core.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 14.3.6.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'typo3/cms-core' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
grep -r 'typo3/cms-core' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
typo3/cms-coreを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade typo3/cms-core to 14.3.6ステージング環境で 14.3.6 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory typo3.org
- advisory typo3.org
- advisory nvd.nist.gov
- advisory github.com
- package github.com
- patch github.com
- patch github.com
- patch github.com
- web github.com
- web github.com
- web news.typo3.com
- web github.com
- web github.com
- web packagist.org