diff -up usbguard-0.7.0/src/Library/SysFSDevice.cpp.kernel-fix usbguard-0.7.0/src/Library/SysFSDevice.cpp
--- usbguard-0.7.0/src/Library/SysFSDevice.cpp.kernel-fix	2017-11-27 15:26:34.895791778 +0100
+++ usbguard-0.7.0/src/Library/SysFSDevice.cpp	2017-11-27 15:29:20.723171663 +0100
@@ -130,6 +130,20 @@ namespace usbguard
     return fd;
   }
 
+  bool SysFSDevice::hasAttribute(const std::string& name) const
+  {
+    struct ::stat st;
+
+    if (::fstatat(_sysfs_dirfd, name.c_str(), &st, AT_SYMLINK_NOFOLLOW) != 0) {
+      if (errno == ENOENT) {
+        return false;
+      }
+      throw ErrnoException("SysFSDevice::hasAttribute", name, errno);
+    }
+
+    return S_ISREG(st.st_mode);
+  }
+ 
   std::string SysFSDevice::readAttribute(const std::string& name, bool strip_last_null, bool optional) const
   {
     USBGUARD_LOG(Trace) << "name=" << name;
diff -up usbguard-0.7.0/src/Library/SysFSDevice.hpp.kernel-fix usbguard-0.7.0/src/Library/SysFSDevice.hpp
--- usbguard-0.7.0/src/Library/SysFSDevice.hpp.kernel-fix	2017-11-27 15:26:34.896791775 +0100
+++ usbguard-0.7.0/src/Library/SysFSDevice.hpp	2017-11-27 15:28:10.778433223 +0100
@@ -42,6 +42,7 @@ namespace usbguard
       const std::string& getName() const;
       const UEvent& getUEvent() const;
       const std::string& getParentPath() const;
+      bool hasAttribute(const std::string& name) const;
       std::string readAttribute(const std::string& name, bool strip_last_null = false, bool optional = false) const;
       void setAttribute(const std::string& name, const std::string& value);
       int openAttribute(const std::string& name) const;
diff -up usbguard-0.7.0/src/Library/UEventDeviceManager.cpp.kernel-fix usbguard-0.7.0/src/Library/UEventDeviceManager.cpp
--- usbguard-0.7.0/src/Library/UEventDeviceManager.cpp.kernel-fix	2017-11-27 15:24:29.034262440 +0100
+++ usbguard-0.7.0/src/Library/UEventDeviceManager.cpp	2017-11-27 15:26:34.897791771 +0100
@@ -580,7 +580,12 @@ namespace usbguard {
     const std::string devtype = uevent.getAttribute("DEVTYPE");
     const std::string action = uevent.getAttribute("ACTION");
 
-    if (subsystem != "usb" || devtype != "usb_device") {
+    /*
+     * We don't care about the event if it's not from the "usb" subsystem.
+     * The device type attribute value is checked later based on the data
+     * read from the sysfs uevent file in the device directory.
+     */
+    if (subsystem != "usb") {
       USBGUARD_LOG(Debug) << "Ignoring non-USB device:" 
                           << " subsystem=" << subsystem
                           << " devtype=" << devtype
@@ -610,8 +615,13 @@ namespace usbguard {
           if (sysfs_device.getUEvent().hasAttribute("DEVTYPE")) {
             const std::string devtype = sysfs_device.getUEvent().getAttribute("DEVTYPE");
             if (devtype != "usb_device") {
-              USBGUARD_LOG(Warning) << sysfs_devpath << ": UEvent DEVTYPE mismatch."
-                << " Expected \"usb_device\", got \"" << devtype << "\"";
+              USBGUARD_LOG(Debug) << sysfs_devpath << ": UEvent DEVTYPE != usb_device. Ignoring event.";
+              return;
+            }
+          }
+          else {
+            if (!sysfs_device.hasAttribute("descriptors")) {
+              USBGUARD_LOG(Debug) << sysfs_devpath << ": UEvent doesn't refer to a device with a descriptors file. Ignoring event.";
               return;
             }
           }