CVE intelligence and bounded remediation
CVE-2021-37626 — Contao is an open source CMS that allows you to create websites and scalable web applications
Contao is an open source CMS that allows you to create websites and scalable web applications. In affected versions it is possible to load PHP files by entering insert tags in the Contao back end. Installations are only affected if they have untrusted back end users who have the rights to modify fields that are shown in the front end. Update to Contao 4.4.56, 4.9.18 or 4.11.7 to resolve. If you cannot update then disable the login for untrusted back end users.
- Severity
- High
- CVSS
- 7.2 (3.1)
- Published
- 2021-08-11
- CISA KEV
- Not currently listed
- Ecosystem
- software/application
- Weaknesses
- CWE-94
Affected products
- contao / contao
- contao / contao / 4.0.0
- contao / contao / 4.1.0
- contao / contao / 4.2.0
- contao / contao / 4.3.0
- contao / contao / 4.5.0
Matched remediation archetype
Command, code, expression, and template injection
This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.
Check exposure
- Trace untrusted values to process execution, interpreters, evaluators, template engines, dynamic imports, and administrative scripting features.
- Determine whether the affected path is reachable across each trust boundary and which service account or host privilege it inherits.
- Review configuration for optional execution features, unsafe compatibility modes, and shell invocation.
Remediate safely
- Replace string-built commands or evaluated code with fixed operations and structured argument APIs that do not invoke a shell.
- Use strict allowlists for operation identifiers and reject unexpected input before it reaches any interpreter.
- Update the affected component and add inert regression tests covering metacharacters, encoding variants, and alternate request paths.
Authoritative sources
Complete CVE record and remediation plan
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