ZyXEL SecuExtender on Windows doesn't work time to time

pista · July 2018

Hi Forum,

we are facing issue with ZyXEL SecuExtender on Windows 10 (v 4.0.2.0).

The SecuExtender is working once and suddenly is not working next time. This happens several users in random time (we can say once per 4 days).

What does it mean?

Once you write your credentials and try to login to SSL VPN via SecuExtender, everything is fine, necessary networks are obtained and you can work. But time by time, the login is successful, you are connected, GUI shows that you have obtained all necessary networks, but you can't reach them (for example web page, etc.).

After a while (hours), nothing changes, we tried to connect again and device was able to connect.

I am going thru SecureExtender logs and SecuExtender Helper logs, but nothing suspicious.

I also tried to disable and enable the 'TAP-Windows Adapter V9 for Zyxel SecuExtender' or kill the session via ZyXEL Admin, once it helped, but another times, it didn't.

Now I am waiting for the issue, to extract the logs for you.

Are you familiar with this issue? Do you have some workaround?

Current Version: V4.31(AAPK.0)

Thanks a lot!
Stefan

Zyxel_Stanley · July 2018

Hi @pista

Welcome to Zyxel community.

After installed SecuExtender, it will installed a virtual interface named “PAT-Windows adapter”.

And after established SSL VPN tunnel, it will add a additional routing in your routing table.

First, you can check the IP address you received.

And you can show the routing table on your windows by “route print” by CLI command.

In this example it has forwarded all of traffic into SSL VPN tunnel. So there is a route like:

Destination 0.0.0.0, Gateway(TAP gateway): 192.168.200.1, Interface: 11.11.11.1.

You can make sure if the routing table has added after SSL VPN tunnel is established.

pista · July 2018

Hi @Zyxel_Stanley @Zyxel_Charlie

I am sending you screenshots of device where it works (left) and device where it suddenly doesn't work (right). I can't see difference between your/ours OK and NOK

can you help?

Only think what I can see, you have in Network connection details IPv4 Default Gateway and IPv4 DNS Server the same.

Can you please give some advice? Where the issue can be?

All devices are working (100), but time to time (maybe 1-2 per day are unable to connect to our AWS servers/tunnels)

Thanks!

Zyxel_Stanley · July 2018

Hi @pista

The SSLVPN routing table still exist on the PC, so SecuExtender still working.

10.0.0.0/16 Gateway:192.168.200.1, interface:192.168.5.3

10.100.0.0/16 Gateway:192.168.200.1, interface:192.168.5.3

But in screen shot(right), there are 2 interfaces are working in the same time.(should be Ether and WiFi)

If IP has changed or shutdown/bring up interface may caused your PC routing table has abnormal behavior.

But this situation will gone if you disconnect/connect SSL VPN tunnel again. Because it will rewrite routing to this PC again.

pista · August 2018

Hi @Zyxel_Stanley

Even the restart of the interface didn't help in this case.

Do you have some evidence, that Windows SecuExtender has issues with stability?
Because it happens quite often for several users.

Just reboot (sometimes twice) of their own device helps and sometimes don't.

Thanks!

Zyxel_Stanley · August 2018

Hi @pista
Per our discussion in private message, please update your test result by private message

pista · August 2018

For others, who will face this (not sure if we are safe now, but looks that it helped a bit):

Looks like upgrade of the firmware helped.

- previous version of firmware: V4.31(AAPK.0)
- current version: V4.31(AAPK.1)ITS-WK27-r84664

ZyXEL SecuExtender on Windows doesn't work time to time

All Replies

Categories

Security Highlight

Security Help Center