GHSA-xjw9-4gw8-4rqx is a critical-severity (CVSS 9.9) Code Injection vulnerability in semantic-kernel. O3 Security confirms whether GHSA-xjw9-4gw8-4rqx is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Microsoft Semantic Kernel InMemoryVectorStore filter functionality vulnerable to remote code execution
Real-World Exposure
semantic-kernelReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Impact:
An RCE vulnerability has been identified in Microsoft Semantic Kernel Python SDK, specifically within the InMemoryVectorStore filter functionality.
Patches:
The problem has been fixed in python-1.39.4. Users should upgrade this version or higher.
Workarounds:
Avoid using InMemoryVectorStore for production scenarios.
References:
Release python-1.39.4 · microsoft/semantic-kernel · GitHub PR to block use of dangerous attribute names that must not be accessed in filter expressions
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | semantic-kernel | all versions | 1.39.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for semantic-kernel. 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 semantic-kernel to 1.39.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-xjw9-4gw8-4rqx 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-xjw9-4gw8-4rqx 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-xjw9-4gw8-4rqx. 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-xjw9-4gw8-4rqx in your dependencies?
O3 detects GHSA-xjw9-4gw8-4rqx across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.