Heuristic Security Weekly Weather Report for WE 8/31/2019

Welcome to the weekly Heuristic Security Internet Weather Report. In this week’s report, suspiciously clearing skies this week from Colorado with a 15% reduction in overall attacks and significant reductions in attacks from Russia, China and the Netherlands. Are attackers reading this report and responding? Who knows…

Weekly Attack Analysis

The first table, Weekly Attacks and Attackers, summarizes the number of attacks from the top 10 countries originating these attacks, and the number of unique attacking IPs per country. In this week’s summary, there was a sharp drop in overall attacks to 30,301, a 15% drop compared to last week. The number of attacking sources was relatively stable at 125 countries compared to 128 for last week.

Items of note: There was a dramatic increase in attacks originating from the US, a 31% rise, while attacks from Russia were down 45% and from the Netherlands down 82%! Does this mean attackers are shifting to compromised servers in the US to launch their attacks in order to better hide their origins? Who knows but the changes are suspicious and we’ll have to see if this trend continues. In other news, China, the Seychelles and Latvia were relatively stable in attacks and attackers, indicating in my mind that these are largely bot driven attacks.

The second table, Weekly Attack Targets, summarizes and sorts the attacks by most frequently targeted port and protocol. The top 4 targets this week were Telnet (23) still on the top by far, TCP port 55555 at #2, SSH (22) rising to #3 and NetBIOS dropping out of the Top 5.

UDP port 34165 is a new addition at #4 on the list. I could not find anything tied to this port in my research – perhaps some new malware is starting to spread? Will have to monitor to see is this trend continues.

Finally, the third chart, Weekly Attacker Trend Report, is a trend chart on changes in attack frequency for the top 5 attacking countries over time. Illustrating my comments from earlier, you can see that there has been a sharp rise in attacks originating from the US, with corresponding drops in overseas attacks. A new trend? We’ll have to see.


So what does this all mean? One, that attacks are pervasive, constant and diverse in origin and target. If you expose it, expect it to be attacked. And if whatever you expose has any vulnerabilities (and what doesn’t these days), expect that they will be exploited as an entree into your network to steal information, steal resources (cryptojacking), extort money (ransomware) or perhaps all of the above.

So what should you do? My recommendations are:

  1. Scan your public IPs to see what ports you may have exposed. Two free tools you can use are the Shields Up! scanner from Gibson Research, as well as the informative Shodan tool. Of course, don’t scan an IP address you do not own.
  2. If you discover open ports, unless you have a legitimate business reason for them to be there (for example 443 for your website), close them in your firewall after confirming what internal system they are forwarding to! If you are scanning your consumer IP, it may be that your router is configured to allow UPnP, which means that your IoT devices (your baby cams, alarm systems, internet-connected toaster, etc.), may be reconfiguring your firewall to open ports for themselves (convenient for them, dangerous for you). Disable UPnP in your router unless you like to live dangerously!
  3. Also, if you have the acumen and a commercial firewall, implement egress filtering in your firewall, in addition to ingress filtering. The SANS Institute Information Security Reading Room has a great paper on Egress Filtering. I highly recommend reading it and implementing it’s recommendations on your firewall – assuming you have the skills and technology to do so. Most consumer routers will not have this functionality.
  4. Finally, make sure your systems are patched! Behind every open port exposed on your firewall is likely to be a service that is unpatched and vulnerable to an exploit of one kind or another. The constant stream of alerts for vulnerabilities and patches just goes to show how vital it is to keep your systems up to date.
  5. If you would like to do further research on IPs that are shown in this report (or from your own network’s firewalls), two resources I recommend are the Wikipedia List of TCP and UDP port numbers and the Internet Storm Center as good starting points.

About this Report

This report does not attempt to discuss the state of attacks and attackers across the entire internet, rather it discusses what I see on my company’s firewalls from my vantage in Colorado and discusses what I believe are general trends and recommended preventative measures based on this information.

Since so many of the attacks today are driven by automated bots scanning the internet for open ports (what I call an attack), I think that the trends I observe locally can be broadly extrapolated to consumer and small business networks across the US. However, as always, the best indication of what is impacting your company’s systems are the results you get by monitoring your own networks. To the extent that you see significantly different results for your network, that may be indicative of a targeted attack on your business (or perhaps on mine?).

About Me

I am an expert in addressing the information security and privacy challenges of complex and fast-paced organizations as both a CISO and adviser to management and the board, in roles ranging from security architect, to risk management, to virtual or permanent CISO. Contact me to discuss how I can help you and your organization achieve your security, risk and privacy objectives.

Please feel free to share or distribute this report. If you have questions on its contents, please feel free to contact me to discuss. And, if you would like to subscribe to have these weekly updates emailed directly to you each Monday, you can do so by signing up on the heuristicsecurity.com website.

News Item

I will be presenting at the Interface-Denver conference on September 5th, 2019 on the topic of CISO/Board communications and challenges.  Stop by and say hello if you happen to be there.

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