Third Party Connections' Security

Do you want your partners trust you directly? Well, do you trust your third party partners directly? When adversaries  are in, they always check different ways to reach more places. So, if one of your trusted third party connection got hacked, it means that there is just a short time they find your connection, and get inside if you did not make your connection secure.

 

Since 2018, we saw that attacks against third party connections increased. Most of them happened because of the small organizations that are giving support in any subject to larger organizations. Because of these small organizations’ low security budget, it is very difficult to secure the network and PCs for them. Most of these organizations do not have a domain structure, security devices for networks and even endpoint protection tools. What I saw while I am working with them that these type of organizations’ users are local admin in their laptops, and only using an antivirus agent to secure the rarely patched laptop. These laptops are being used to connect to other organizations, and sometimes to keep some sensitive data about of these organizations. They are very close to get hacked, but you must not get this risk while working with them.

Third Party Connection Management in Organizations

 

Especially in large organizations, since policies not working properly; and maybe since there is no any policy for third party connections, circulation of staff and sudden and fast developing projets, teams can create third party connections how it is easy at that time for them. This creates an unmanaged third party connections structure and so, it becomes worse day by day.

 

I remember we spent at least four months to fix the third party connections in a large organization. Dozens of leased lines reaching directly to different networks inside, hundereds of S2S VPNs established years ego, has certificates with low key sizes, and etc. Lack of a basic policy like third party connections policy causes a huge waste of time and effort to fix it.

 

What to Do?

 

Whoever you are connecting, or connecting to you, you should minimize threats. Because, all organizations are the target for hackers and they all can be hacked. You should not trust anybody else about security. You should understand what security controls they apply in the organization. If they have some weaknesses to determine the attacks made to themselves, it will put you at risk.

 

Create a 3rd party DMZ network. This is important because these 3rd party PCs should not connect to your network directly from any zone in your firewall. These PCs are something you cannot trust directly. So, at least, a 3rd party DMZ should be created to connect and control these type of connections. If there is no any 3rd party zone and policy, in a long period of time, with some of the activities explained at the beginning, you can see many different 3rd party organizations are connecting to your network from many different zones. And it will be something unmanagable day by day. For the beginning, I suggest to create a different zone for leased line connections to the internet facing firewall, and control these connections policies there. Also, a different firewall should be implemented for S2S VPN connections. It is important to receive these connections in a different firewall and control their connections.

 

You should use a vendor management program. It helps you to reduce the risk, by collecting more and more information about your third party connection and should be sure they comply with standards and regulations.

 

You should know what security controls, endpoint security (antivirus, EDR, encryption, etc.) and data leakage prevention methods do your third party connection imply to its users. Mostly, if you do not give a laptop to users that will connect to your network, third party organiztions’ staff uses their own or that company’s PCs. That means, these computer will be connected to your network most of the time, and these PCs will contain your some sensitive information. So, it is important to know whether they are protecting these PCs while working with you.

 

Screen recording is also a very useful tool. It is impossible to watch directly every consultant’s actions on your network. Most of the time they work on your test servers on test zones, and unfortunately, sometimes they can work directly on production zone or can reach to production zone because of the lack of controls. A screen recording tool will be an important deterrent action for you.

 

MFA is must. Multi-factor authentication should be used to connect your network. Mostly I suggest time based MFA tools to use. Any time a security incident occurs in 3rd party’s network, MFA will be important to secure you.

 

 

 

Host-Based Firewalls - A Possible Nightmare for IT Pros

With increasing remote workforce process during Covid-19, clients are now more independent with their laptops and mobile phones that also being used for personal usage besides organizational usage. Not only workers, but also computers and data are now outside the organization and most of the protection layers such as firewall and IPS. Vulnerabilities and attacks continue to surface but remote users’ connection and VPN also create troubles for IT teams to patch  and protect the clients.

 

Host-based firewalls help security professionals in many subject. Firstly, it controls the incoming and outgoing traffic, so becomes a very critical defense layers. For example, security pros may want to block all inbound connection to the client host initiated from outside. This is a very basic protection on some kinds of malwares.

Some sensitive applications like Swift, should be isolated from the network in the organization. But sometimes it is not an effective solution to create vlans for a few PCs or servers. For the situations like that, host-based firewalls are true saviors. These sensitive PCs and servers can be isolated with host-based firewalls. Since most of the antivirus agents also includes host-based firewall feature, this solution becomes easier and more logical. 

Meanwhile, organizations should not make it a habit. In large organizations having thousands of PCs and servers, this isolations on host-based firewalls can easily turn into a nightmare, since hundreds of rules have to be written. If these rules are not followed properly, also with the circulation in the administration team, a possible mixed rules can harm PCs and network more than they protect. It is inevitable that every rule for each small groups makes the rule list more complex, and it becomes more possible to make a mistake while adding new rules.

So, even if host-based firewalls are important and valuable solutions, they should be used as needed, and should not be a regular solution for isolation situations. 

"MUST" Practices for AntiVirus

Last week, I hearth that an organization did not add antivirus agent to their PC image. They are formatting the PC with their image, then connecting to the network and waiting for the sccm installing the antivirus software to the PC. Also, for remote users working on the field, some contracted partners are formatting the PCs since these users cannot come to the company, they then join to the network via VPN after formatting and keeps working. Meanwhile, the IT team is waiting for the sccm install the antivirus software, but because of the VPN network, most of the time it fails. PC keeps working on the network for days. 

While I was sharing this situation with some friends in the industry, some of them also said that it is a normal process for the organizations. So, I wanted to write this article. 

A few months ago, I shared a post about falling of the AV. It is true that AV softwares are not very efficient in recent years. There are many other measures need to be taken to protect the endpoints. However, most of these measures are for APT attacks. As everyone says, and also I touch in the article, attackers' profile and techniques has changed a lot, since the times AV was popular and successful. But, despite all these situations, nobody can say that AVs are not necessary anymore. Organizations does not face attackers that using highly advanced techniques and tools only. There are still many script kiddies and those trying to learn hacking. These people are always looking for easy vulnerabilities to hack. It is very great possibility they find you. 

Another subject about AV, because of the hash databases downloaded, they can protect users for many of the malicious events, also while they are offline, or while they are not connected to the office. 

Even, most of the AV softwares are improving themselves with behavioral and AI capabilities. So, these can also detect and stop some of the APT attack phases. 

I am also curious your comments, but my opinion is an AV is still indispensable for all organizations. So, I want to some best (must) practices for using AV in an organization;

        - An AV software should be installed on all devices. Clients should be periodically followed whether has AV on it or not. If it is possible, a NAC solution should be positioned and PCs that does not have AV should be blocked.

        - AV solution should be centrally managed. So, updates can be managed centrally and out of date clients can be followed. 

        - Administrators should make sure all clients are sending logs properly. It is very important to response a suspicious situation quickly. 

        - AV software should be updated periodically. Meanwhile, administrators also should be sure that all clients are getting the latest updates properly.

        - AV software should be included into the PC and servers' regular images. When a PC formatted and re-installed, it should include AV before connecting the network. 

        - Users should not be able to disable the AV services and agent. Tamper protection and an uninstall password should be used and should be stored in a password management system. 

        - Malicious files should be blocked and quarantined to be analyzed by the administrators. 

        - Audit logs should be collected properly. Administrators should login to the software only by their own usernames. Generic usernames should not be used. 

        - Too many exceptions should not be given. If needed, exceptions should be given only as stated by the vendors. 

        - If including, host-based IDS should be enabled on the AV agent. 

wget with Powershell

 function global:wget($Address, [switch]$NoCache)

{

 $client = New-Object Net.WebClient

 $proxy = New-object System.Net.WebProxy "10.0.0.10:8080"

 $proxy.Credentials = New-Object System.Net.NetworkCredential ("DOMAIN\user", "password") 

 $client.proxy=$proxy

 $Client.Headers.Add("user-agent", "Windows Powershell WebClient Header") 

 if ($NoCache) {

  # doesn't use the cache at all

  $client.CachePolicy = New-Object Net.Cache.RequestCachePolicy([Net.Cache.RequestCacheLevel]::NoCacheNoStore)

 }

 

 $client.DownloadString($Address)

}

 

wget -Address "http://be4sec.blogspot.com" -NoCache

FireEye NX SmartVision SC Killswitch

SmartVision is the lateral movement detection module of the network security product (NX) of FireEye. There are too many documents and descriptions about it on FireEye's website, so I will not touch on it here. I just want to explain what SC Killswitch is in the SmartVision configuration, since there is no any explanation about it anywhere.

The SC Killswitch is not a user configurable setting, so there is no any command to enable or disable it even if you see it is like configurable in show menu.

#show smartvision config

It is something about status of the SmartVision module. Sometimes, some Security-Contents may have to restart SmartVision module. This SC Killswitch value indicates whether SmartVision module should be restarted or not. If this value is no;

SC Killswitch: no

this simply indicates that there is no need to restart SmartVision module.