NetGuard: Exported activity allows unauthorized firewall deactivation
NetGuard, a no-root firewall app for Android, has insecure permissions in its exported activity ActivityMain in version 2026080101 (versionName 2.337). An app installed on the same device without any Android permissions can send a boolean extra named "Approve" to switch the firewall off without user interaction, and the change persists across force-stop and reboot. The CVE record describes a forced device reset or denial of service, while the advisory reports the unauthorized firewall deactivation and VPN service teardown.
Marcel Bokhorst (FairCode BV) · NetGuard
