GHSA-w4rc-rx25-8m86
CRITICALGHSA-w4rc-rx25-8m86 is a critical-severity (CVSS 9.8) CWE-116 vulnerability in symfony/symfony. O3 Security confirms whether GHSA-w4rc-rx25-8m86 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Improper Input Validation in Symfony
Real-World Exposure
symfony/symfony🐘symfony/symfony🐘symfony/var-exporter🐘symfony/var-exporterReal-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
An issue was discovered in Symfony before 4.2.12 and 4.3.x before 4.3.8. The VarExport component incorrectly escapes strings, allowing some specially crafted ones to escalate to execution of arbitrary PHP code. This is related to symfony/var-exporter.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | symfony/symfony | ≥ 4.2.0&&< 4.2.12 | 4.2.12 |
| 🐘Packagist | symfony/symfony | ≥ 4.3.0&&< 4.3.8 | 4.3.8 |
| 🐘Packagist | symfony/var-exporter | ≥ 4.2.0&&< 4.2.12 | 4.2.12 |
| 🐘Packagist | symfony/var-exporter | ≥ 4.3.0&&< 4.3.8 | 4.3.8 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for symfony/symfony. 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 symfony/symfony to 4.2.12 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-w4rc-rx25-8m86 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 GHSA-w4rc-rx25-8m86 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 GHSA-w4rc-rx25-8m86. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-w4rc-rx25-8m86 in your dependencies?
O3 detects GHSA-w4rc-rx25-8m86 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.