Vulnerability Database

374,644

Total vulnerabilities in the database

Craft CMS: Arbitrary file read via SplFileObject in non-sandboxed template contexts — craftcms / cms

Incomplete List of Disallowed Inputs

The create() Twig function (introduced in 5.9.0) allows instantiation of arbitrary PHP classes from template code, restricted only by a 5-entry blocklist. SplFileObject is not in the blocklist, enabling arbitrary file read, including .env (security key, DB credentials) and the passwd file from non-sandboxed Twig template contexts, such as entry type title formats and URI formats.

The sandbox correctly blocks create() in system email templates, so this finding applies only to admin-configured, non-sandboxed contexts that require allowAdminChanges=true.

Prerequisites

  • Admin access to the Craft control panel
  • allowAdminChanges must be true (default in dev/staging, recommended false in production)
  • Admin must be able to edit entry type settings (title format, URI format)
  • Any user who subsequently creates an entry in the affected section triggers the file read

Limitations

  • Requires admin-level access: not exploitable by low-privilege users
  • allowAdminChanges must be true: production best practices recommend false, which prevents entry type configuration changes
  • Per Craft’s own severity guidelines, findings requiring allowAdminChanges=true are rated low
  • The create() function is blocked by the Twig sandbox, so this cannot be exploited via system email templates or any other sandboxed context

Impact

An admin user (or an attacker who has compromised an admin account) can read arbitrary files from the server filesystem by setting a malicious entry type title format using create('SplFileObject', ['/path/to/file']). In production environments, this exposes .env files containing the CRAFT_SECURITY_KEY, database credentials, API keys, and other secrets. The file contents are rendered as entry titles visible to any user with permission to view entries in the affected section.

The impact is limited by the requirement for admin access and allowAdminChanges=true.

  • Published: Aug 6, 2026
  • Updated: Aug 7, 2026
  • GHSA: GHSA-957r-qf9p-67xw
  • Severity: Medium
  • Exploit:
  • CISA KEV:

No technical information available.

CWEs:

Frequently Asked Questions

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.