CVE-2020-11067
HIGHCVE-2020-11067 is a high-severity (CVSS 8.8) Deserialization of Untrusted Data vulnerability in typo3/cms-core. O3 Security confirms whether CVE-2020-11067 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Insecure Deserialization in Backend User Settings in TYPO3 CMS
Real-World Exposure
typo3/cms-core🐘typo3/cms-core🐘typo3/cms🐘typo3/cmsReal-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
In TYPO3 CMS 9.0.0 through 9.5.16 and 10.0.0 through 10.4.1, it has been discovered that backend user settings (in $BE_USER->uc) are vulnerable to insecure deserialization. In combination with vulnerabilities of third party components, this can lead to remote code execution. A valid backend user account is needed to exploit this vulnerability. This has been fixed in 9.5.17 and 10.4.2.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | typo3/cms-core | ≥ 9.0.0&&< 9.5.17 | 9.5.17 |
| 🐘Packagist | typo3/cms-core | ≥ 10.0.0&&< 10.4.2 | 10.4.2 |
| 🐘Packagist | typo3/cms | ≥ 10.0.0&&< 10.4.2 | 10.4.2 |
| 🐘Packagist | typo3/cms | ≥ 9.0.0&&< 9.5.17 | 9.5.17 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for typo3/cms-core. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update typo3/cms-core to 9.5.17 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-11067 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.
How O3 protects you
O3 pinpoints whether CVE-2020-11067 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2020-11067. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2020-11067 in your dependencies?
O3 detects CVE-2020-11067 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.