GHSA-mmcv-fvq8-r9x3
CRITICALSymfony XML decoding attack vector through external entities
Blast Radius
symfony/symfonyReal-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 XMLEncoder component of Symfony 2.0.x fails to disable external entities when parsing XML. In the Symfony2 framework the XML class may be used to deserialize objects or as part of a client/server API. By using external entities it is possible to include arbitrary files from the file system.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | symfony/symfony | ≥ 2.0.0&&< 2.0.11 | 2.0.11 |
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 2.0.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-mmcv-fvq8-r9x3 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-mmcv-fvq8-r9x3 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-mmcv-fvq8-r9x3. 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-mmcv-fvq8-r9x3 in your dependencies?
O3 detects GHSA-mmcv-fvq8-r9x3 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.