CVE-2021-37626 — core-bundle
HIGHCVE-2021-37626 is a high-severity (CVSS 7.2) Code Injection vulnerability in contao/core-bundle. A fix is available for contao/core-bundle — see the affected versions and patch details below.
PHP file inclusion via insert tags
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2021-37626 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 385,738 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
contao/core-bundle🐘contao/core-bundle🐘contao/core-bundle🐘contao/contao🐘contao/contao🐘contao/contaoReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | contao/core-bundle | ≥ 4.0.0&&< 4.4.56 | 4.4.56composer require contao/core-bundle:^4.4.56 |
| 🐘Packagist | contao/core-bundle | ≥ 4.5.0&&< 4.9.18 | 4.9.18composer require contao/core-bundle:^4.9.18 |
| 🐘Packagist | contao/core-bundle | ≥ 4.10.0&&< 4.11.7 | 4.11.7composer require contao/core-bundle:^4.11.7 |
| 🐘Packagist | contao/contao | ≥ 4.0.0&&< 4.4.56 | 4.4.56composer require contao/contao:^4.4.56 |
| 🐘Packagist | contao/contao | ≥ 4.5.0&&< 4.9.18 | 4.9.18composer require contao/contao:^4.9.18 |
| 🐘Packagist | contao/contao | ≥ 4.10.0&&< 4.11.7 | 4.11.7composer require contao/contao:^4.11.7 |
Affected Products
contaocontaoDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for contao/core-bundle, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update contao/core-bundle to 4.4.56 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-37626 is resolved across your whole dependency graph.
Workarounds
Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does.
Frequently Asked Questions
Is CVE-2021-37626 in your dependencies?
Find it across Packagist, including transitive dependencies.