ID:
SYSCLASSNET_VPNCategory: Interfaces Status in RKNHardering 2.10.0: Active check Role in the verdict: High
This page describes the actual implementation in RKNHardering 2.10.0. It distinguishes what can be done without root, what requires root, and where a mitigation only reduces one signal without hiding the VPN as a whole.
detectSysclassnetVpn() calls stat() only for /sys/class/net/{tun0,tun1,utun0,wg0,ppp0,xfrm0} and lists the names it finds. This is a narrower duplicate of part of sysfs-vpn-leak, retained as a separate diagnostic ID.
At least one of the six fixed /sys/class/net/<name> directories exists.
Kernel sysfs exposes a network device with a typical VPN name. A match is treated as a high-confidence local artifact.
How the line affects the report: The line sets detected=true and is treated as a high-confidence local indicator.
The check does not inspect type, mtu, or operstate, and does not cover nonstandard names. SELinux may block traversal, in which case the line is absent even when the interface exists. Conversely, a disabled but not deleted network device still triggers the check.
This line must be evaluated together with neighboring signals. A clean result from a single API does not simultaneously cover Java Binder, libc, raw netlink/syscalls, procfs/sysfs, local sockets, and server-side indicators.
The most reliable non-root approach is not to create a VPN interface on the phone being tested: move the tunnel to a router, travel router, separate gateway phone, or another network node. Per-app bypass in VpnService changes the route used by the selected app, but establish() still creates a system VPN interface, so local interface checks may continue to trigger. A local HTTP/SOCKS proxy mode without TUN can sometimes remove this specific vector, but it leaves listening ports and proxy settings and does not cover apps that ignore the proxy.
Laboratory-grade hiding usually requires both a system Java layer and one native backend. With VPNHide, that means the APK plus Vector/LSPosed scoped only to System Framework, and exactly one of kmod, KPM, or Zygisk. For a check that may use a direct syscall or netlink, kmod or KPM is preferable: a userspace Zygisk hook can be bypassed and leaves traces inside the process. Review the VPNHide coverage map first, and download builds only from the official release page. VPNHide Next claims broader coverage, but it also warns about possible boot loops and kernel panics; test it only on a dedicated device. Verify that the solution covers not only readdir() but also a direct stat("/sys/class/net/tun0"); otherwise this exact-path probe bypasses a filtered directory listing.
adb shell 'for n in tun0 tun1 utun0 wg0 ppp0 xfrm0; do [ -e /sys/class/net/$n ] && { echo "[$n]"; cat /sys/class/net/$n/type /sys/class/net/$n/mtu /sys/class/net/$n/operstate 2>/dev/null; }; done'
After any change, force-stop both RKNHardering and the VPN client, start them again, and repeat the full scan. Zygisk, Xposed, and kernel modules usually require a reboot. Compare not only this line but also neighboring signals: a partial hook often creates inconsistencies between APIs.
The probe itself runs with ordinary app permissions and does not request root. The ADB commands below are for orientation only: adb shell runs under a different UID and may see either more or less than the app process. The decisive test is to run the check again after a force-stop.
Broad sysfs substitution may disrupt NetworkStack, netd, and OEM services. Do not change ownership or permissions of sysfs files; the kernel creates them.
Revert the most recent change: disable the added module or rule through its normal manager, reboot the device, and repeat the baseline scan. Do not layer another hook on top of an unknown state.
High. Verified from the exact stat() calls and the HIGH_CONFIDENCE mapping.
The status of a third-party solution does not automatically carry over to this device. A module developer’s claim is only the initial hypothesis; confirmation requires a reproducible RKNHardering result on the specific Android version, firmware, and kernel.
native_signs_probe.cpp — native probe implementation.VpnNativeDetectorChecker.kt — deep VPN verdict and confidence.NativeSignalId.kt — complete ID registry.NativeSignalCatalog.kt — category, slug, and line mapping.Related signals: sysfs-vpn-leak, tuntap-type, proc-net-dev-vpn.