Understanding Network Access in Windows App Containers
Summary: Google Project Zero's James Forshaw found a configuration issue in the Windows Firewall that let an AppContainer process bypass network restrictions and reach services on localhost and intranet resources in an Enterprise. Microsoft marked the issue WontFix, deciding it did not meet the bar for a security bulletin, and Forshaw published the undocumented details of how the firewall restricts AppContainer network access through the Windows Filtering Platform.
What you should know: A sandbox escape that grants an AppContainer access to localhost services and enterprise intranet resources is shipping unfixed by Microsoft's own decision, so the boundary your sandboxed applications rely on may not hold.
Read the original at Google Project Zero ↗
- Topics
- Vulnerabilities & Patching
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