Welcome to the weekly Heuristic Security Internet Weather Report. In this week’s report, the Cat 5 hurricane of attacks originating from the Seychelles has abated, with attacks from the US and Russia back to taking the top spots. Also, unusual port activity this week.

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, attacks were down sharply to 40,941, a 23% drop compared to last week. The most significant part of that drop was the collapse of attacks originating from the Seychelles. Attacks from the US were up sharply this week, followed by Russia. The number of attacking sources was down a bit at 121 originating countries.


The second table, Weekly Attack Targets, summarizes and sorts the attacks by most frequently targeted port and protocol. Telnet (port 23) continues to be the leader by far but there are two new unusual entries this week – STUN (Simple Traversal of UDP Through NAT port 3478) UDP and port 10854 UDP. STUN in particular is used by Ubiquiti Unifi Cloud Access – is this a targeted attack on Unifi WiFi networks? There are no reports on this that I could find in the press. As for port 10854 this is just a random unassigned port – why it is getting pounded this week is beyond me.

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. As discussed above, the flurry of attacks from the Seychelles almost completely abated this week with attacks from US taking up the slack.

Recommendations

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.