Pulse Secure and the bells around it

So you have implemented Pulse Secure as a VPN-solution? Well, here are somethings that just about every consulting firm or department eventually will ask you to implement along-side it – so the Pulse Secure client works. The details aren’t here – but more the general mindset, what todo when – but not exactly how every scheduled task / script looks like. Hopefully this will guide you – and potentially arm you with possibility to fix more problems in the future. 

Triggers

First things first – a great way to trigger activity is based on Pulse Secure events – described more in detailed on their admin-guide. Common event-ids that might be useful are;

Disconnect – 302 / 106

Connect – 312 (not documented)

To create a scheduled task for any event – simply find a sample event a select to create a Scheduled Task;

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In addition to Application and Services log / Pulse Secure, you can always find Microsoft-Windows-NetworkProfile/Operational. This contains great entries for what network you connect to, what network profile type of profile you connect to. Event-id 1000 within NetworkProfile is simply that you are connected to a new network as a sample.

Actions

What actions will be asked to run when these events happen?

Re-register DNS

Name-resolution for the helpdesk not quick-enough to connect to your laptop once you are connected? On event Connect (detected by Pulse Secure/Operational and the event id 312) you can simply have the scheduled task run the command-line – and this will mitigate some stuff. 

ipconfig /registerdns

DNS Suffix search list

Pulse normally appends the searchlist of the DNS-suffixes that are set on your client. It also fails to clean this up properly – so name resolution after a disconnect can be challenging. A tidy way todo this would be to trigger on a disconnect (primarily event id 302 within Pulse Secure, but also 106 might be applicable) and then do a sweep. Sample code;

$dnsCGSetting = Get-DnsClientGlobalSetting
$SList = $dnsCGSetting.SuffixSearchList
If ([string]::IsNullOrEmpty($SList) -or $SList -eq "OK.suffix")
{
#donothing
}
Else{
Set-DnsClientGlobalSetting -SuffixSearchList @('')
}

SuperUser has some options if you have a longer list of suffixes to handle..

Host-checker antivirus check

Did someone implement a host-checker and decided something needs to be up-2-date? Like antivirus definitions? Use trigger NetworkProfile with EventID to identify that a device has successfully connected to a network, and then do a check which network – and if not the corporate one – start up the processes to ensure users can avoid having a failed connect.

Sample functions (to check what network and do a validation of Defender AV Signature) – in VBscript as this was to be firing of quite heavily on all endpoints.

Private Function NetConnectionProfileName(Network)
	Dim objWMIService
	Dim colItems

	NetConnectionProfileName = False
	
	On Error Resume Next
	Set objWMIService = GetObject("winmgmts:\\.\root\StandardCimv2")

	Set colItems = objWMIService.ExecQuery("Select * From MSFT_NetConnectionProfile")

	For Each objItem in colItems
		if objItem.Name = Network Then 
			NetConnectionProfileName= True
		End if 
	Next

	Set objWMIService = Nothing

End Function

Private Function DefenderSignatureUpdate
	Dim objWMIService
	Dim colItems
	
	DefenderSignatureUpdate = False

	On Error Resume Next
	Set objWMIService = GetObject("winmgmts:\\.\root\Microsoft\Windows\Defender")

	Set colItems = objWMIService.ExecQuery("Select * From MSFT_MPComputerStatus")
	Wscript.echo "Definition-update: " & Left(objItem.AntivirusSignatureLastUpdated,8) & "Today: " & year(now())&right("00" & month(now),2)&right("00" & Day(now),2)
	For Each objItem in colItems
		if Left(objItem.AntivirusSignatureLastUpdated,8) = year(now())&right("00" & month(now),2)&right("00" & Day(now),2) Then 
			
			DefenderSignatureUpdate = True
		End if 
	Next



	Set objWMIService = Nothing

End Function

A similiar way within Powershell to detect a Domain-profile is posted on Twitter:

Windows Firewall profile doesn’t always switch to Domain when you use a third-party VPN client

This isn’t really an action. You could most likely trigger something off the event ids – however, Microsoft has documented a great article about this problem. Pulse allegedly fixed this in a really old-version of the client, but to this day noone is happy about it. Set the two workarounds as part of your baseline for devices connecting via VPN – and you should be good. Pulse (now owned by Ivanti) will not be fixing this it seems. As far as I can tell Pulse adds routes, and then doesn’t notify Windows in anyway that triggers a rediscovery for Domain-connections.

Microsoft states:

  • First, disable Domain Discovery negative cache by adding the NegativeCachePeriod registry key to following subkey: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\NetLogon\Parameters Name: NegativeCachePeriod
    Type: REG_DWORD
    Value Data: 0 (default value: 45 seconds; set to 0 to disable caching)
  • If issue doesn’t resolve, further disable DNS negative cache by adding the MaxNegativeCacheTtl registry key to the following subkey: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Dnscache\Parameters Name: MaxNegativeCacheTtl
    Type: REG_DWORD
    Value Data: 0 (default value: 5 seconds; set to 0 to disable caching)

Force a new network-profile

Your client still skipping around and not getting stuff right? Well, you can switch over to a Private Profile. Public is by default, and Domain requires that a Active Directory is reachable (process documented in previous article from Microsoft) – but Private you can switch to.

See this one-liner to detect a specific network and switch the Network Profile

Get-NetConnectionProfile -Name 'networkname' | Set-NetConnectionProfile -NetworkCategory Private

Group Policy Preference and Scheduled Tasks

For some reason it’s always the details in the basics that are the longest hurdle to get over. This particular topic is something that always needs to be re-googled before the last details are sorted out.

Purpose

To create a schedule task to either run as the system-account or the interactive user via Group Policy Preference.

The detail:

When resolving SYSTEM the normally resolved identity is BUILTIN\SYSTEM. Interactive is normally not able to resolve at all. This normally results in the following error client side when attempting to apply the Group Policy

‘0x80070534 No mapping between account names and security IDs was done.’

What should be done?

Click the Change User or Group and select the domain of your environment, and proceed to select the Builtin-container. This will resolve both Interactive (running in the user context of the logged on user) and system to NT Authority.

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End-result;

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or

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