Open Redirect in Drupal core (CVE-2026-55806)
Summary
Vulnerability in Drupal core (CVE-2026-55806). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
Drupal core ships a rebuild.php front controller that can be used to rebuild Drupal (clearing the caches and rebuilding the container) when the site is in an unexpected condition.
This script doesn't correctly check the Host header against the list of trusted host patterns. This could result in cache poisoning or a redirect to an attacker-controlled domain.
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-2026-55806 has been found in Drupal core.
Risk of unauthorized operations or information disclosure. CVSS score: 5.9/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Drupal core CVE-2026-55806" on the vendor's site.
CVE-2026-55806 (Drupal core) — CWE-601 / CVSS v3 5.9
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
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-601) exists in Drupal core.
Check the vendor advisory for the affected versions of Drupal core.
Severity: Medium (CVSS 5.9/10). Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
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. Audit SBOM/dependencies 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
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Drupal core を使っているサービスとバージョンを洗い出す。
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2Post-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
- web drupal.org
- web nvd.nist.gov
- web github.com