TypeError on /device/register [PUT] endpoint - Need help interpreting traceback

Pritunl Pritunl VPN
1

Hi,
I’m seeing the following error in our Pritunl logs and would like help understanding the cause and potential impact. Here’s the full traceback (sensitive data obfuscated):

[pritunl-vpn-host-<obfuscated>][2025-07-21 18:53:15,563][ERROR] Exception on /device/register/<obfuscated>/<obfuscated>/<obfuscated> [PUT]
Traceback (most recent call last):
  File "/usr/lib/pritunl/usr/lib/python3.9/site-packages/flask/app.py", line 2190, in wsgi_app
    response = self.full_dispatch_request()
  File "/usr/lib/pritunl/usr/lib/python3.9/site-packages/flask/app.py", line 1486, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "/usr/lib/pritunl/usr/lib/python3.9/site-packages/flask/app.py", line 1484, in full_dispatch_request
    rv = self.dispatch_request()
  File "/usr/lib/pritunl/usr/lib/python3.9/site-packages/flask/app.py", line 1469, in dispatch_request
    return self.ensure_sync(self.view_functions[rule.endpoint])(**view_args)
  File "/usr/lib/pritunl/usr/lib/python3.9/site-packages/pritunl/auth/app.py", line 10, in _wrapped
    return call(*args, **kwargs)
  File "/usr/lib/pritunl/usr/lib/python3.9/site-packages/pritunl/handlers/device.py", line 48, in device_register_put
    usr.device_register(device_id, reg_key)
  File "/usr/lib/pritunl/usr/lib/python3.9/site-packages/pritunl/user/user.py", line 1395, in device_register
    if utils.const_compare(device.get('reg_key', ''), reg_key):
  File "/usr/lib/pritunl/usr/lib/python3.9/site-packages/pritunl/utils/misc.py", line 397, in const_compare
    if len(x) != len(y):
TypeError: object of type 'NoneType' has no len()

I’m not sure what specifically triggers this error. From the traceback, it seems like the reg_key from the device object is None, which causes a failure in the const_compare() function.

Could you please clarify:

  1. Under what circumstances could this error occur?
  2. Is this expected behavior under certain conditions (e.g. client misuse, expired state, auth failure)?
  3. Does this indicate a misconfiguration on the server or client side?
  4. Is there any recommended way to handle or suppress this error?

Thanks in advance for your help!

2

This appears to be an issue fixed in a later release. If a device with the same name was registered it would invalidate it and make it unable to register. I think it was fixed in v1.32.3719.89 but may have been a newer release. The server should be updated and those devices deleted. Verify in the hosts tab that the running version is the latest release.

3

Hi Zach!
My hosts are running version v1.32.3805.95.

4

Try deleting all the pending devices shown on the dashboard tab.

5

Hi,
I’ll follow your guidance.
Thanks, Zach!