CVE-2019-11831
CRITICALCVE-2019-11831 is a critical-severity (CVSS 9.8) Path Traversal vulnerability in typo3/phar-stream-wrapper. O3 Security confirms whether CVE-2019-11831 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Directory Traversal in typo3/phar-stream-wrapper
Blast Radius
typo3/phar-stream-wrapper🐘typo3/phar-stream-wrapper🐘drupal/core🐘drupal/core🐘drupal/core🐘drupal/drupal🐘drupal/drupal🐘drupal/drupalReal-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
The PharStreamWrapper (aka phar-stream-wrapper) package 2.x before 2.1.1 and 3.x before 3.1.1 for TYPO3 does not prevent directory traversal, which allows attackers to bypass a deserialization protection mechanism, as demonstrated by a phar:///path/bad.phar/../good.phar URL.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | typo3/phar-stream-wrapper | ≥ 2.0.0&&< 2.1.1 | 2.1.1 |
| 🐘Packagist | typo3/phar-stream-wrapper | ≥ 3.0.0&&< 3.1.1 | 3.1.1 |
| 🐘Packagist | drupal/core | ≥ 7.0.0&&< 7.67.0 | 7.67.0 |
| 🐘Packagist | drupal/core | ≥ 8.0.0&&< 8.6.16 | 8.6.16 |
| 🐘Packagist | drupal/core | ≥ 8.7.0&&< 8.7.1 | 8.7.1 |
| 🐘Packagist | drupal/drupal | ≥ 7.0.0&&< 7.67.0 | 7.67.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for typo3/phar-stream-wrapper. 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/phar-stream-wrapper to 2.1.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2019-11831 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-2019-11831 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-2019-11831. 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-2019-11831 in your dependencies?
O3 detects CVE-2019-11831 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.