CVE-2020-25768 — core-bundle
MEDIUMCVE-2020-25768 is a medium-severity (CVSS 5.3) Improper Input Validation vulnerability in contao/core-bundle. A fix is available for contao/core-bundle — see the affected versions and patch details below.
Contao Insert tag injection in forms
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2020-25768 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/contao🐘contao/contao🐘contao/contao🐘contao/core-bundleReal-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
Impact
It is possible to inject insert tags in front end forms which will be replaced when the page is rendered.
Patches
Update to Contao 4.4.52, 4.9.6 or 4.10.1.
Workarounds
Disable the front end login form and do not use form fields with array keys such as fieldname[].
References
https://contao.org/en/security-advisories/insert-tag-injection-in-forms
For more information
If you have any questions or comments about this advisory, open an issue in contao/contao.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | contao/core-bundle | ≥ 4.0.0&&< 4.4.52 | 4.4.52composer require contao/core-bundle:^4.4.52 |
| 🐘Packagist | contao/core-bundle | ≥ 4.5.0&&< 4.9.6 | 4.9.6composer require contao/core-bundle:^4.9.6 |
| 🐘Packagist | contao/contao | ≥ 4.0.0&&< 4.4.52 | 4.4.52composer require contao/contao:^4.4.52 |
| 🐘Packagist | contao/contao | ≥ 4.5.0&&< 4.9.6 | 4.9.6composer require contao/contao:^4.9.6 |
| 🐘Packagist | contao/contao | ≥ 4.10.0&&< 4.10.1 | 4.10.1composer require contao/contao:^4.10.1 |
| 🐘Packagist | contao/core-bundle | ≥ 4.10.0&&< 4.10.1 | 4.10.1composer require contao/core-bundle:^4.10.1 |
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 4.4.52 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-25768 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Frequently Asked Questions
Is CVE-2020-25768 in your dependencies?
Find it across Packagist, including transitive dependencies.