Vulnerability in Drupal core (CVE-2026-55804)
Summary
Vulnerability in Drupal core (CVE-2026-55804). Confidential information can be exposed externally.
Original description
The description as published by the source.
Drupal core contains a chain of methods that could be exploitable when an insecure deserialization vulnerability exists on the site. This so-called "gadget chain" presents no direct threat, but is a vector that can be used to achieve remote code execution or SQL injection if the application deserializes untrusted data due to another vulnerability.
This issue is not directly exploitable.
This issue is mitigated by the fact that in order for it to be exploitable, a separate vulnerability must be present to allow an attacker to pass unsafe input to unserialize().
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-2026-55804 has been found in Drupal core.
Confidential information can be exposed externally. 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-2026-55804" on the vendor's site.
CVE-2026-55804 (Drupal core) — CWE-915 / CVSS v3 5.9
Attack vector: remote (network-reachable) / 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-915) exists in Drupal core.
Check the vendor advisory for the affected versions of Drupal core.
Severity: Medium (CVSS 5.9/10). Confidential information can be exposed externally.
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