Recently Discovered ICS Vulnerability

Earlier this week, ICS-CERT announced that a new vulnerability was discovered in ICS products made by Endress+Hauser. The vulnerability affects the DTM library used by Endress+Hauser HART-based field devices in the FDT/DTM Frame Application. If a specially crafted packet manages to exploit the vulnerability, the DTM Frame Application will become unresponsive as result of a buffer overflow. Endress+Hauser has released a security update addressing this issue. Despite the fact that we haven’t observed this vulnerability being exploited in the wild, we highly recommend applying the patch by Endress+Hauser as soon as possible.
To minimize the risk of an ICS device being compromised by an attacker, be sure to consider the following general recommendations:
  • Discover and document – You can’t protect a system if you don’t know it exists. Take some time to identify and document all of the legacy and unsupported operating systems in your network.
  • Isolate  Segmenting the ICS system will reduce the risk of it being compromised by an attacker. Take some time to verify that it is inaccessible from any unnecessary business/ user networks.
  • Update and secure – Install all available patches and updates. Be sure that you are notified of any updates to the operating system, firmware and any installed applications.
  • Perform thorough log analysis – Implement some sort of centralized logging platform to ensure you have the ability to detect any anomalies that occur within these systems.
  • Leverage the use of an ICS honeypot – Creating a HoneyPot ICS device will help you discover suspicious activity within your network before it affects a production system.

Just a Quick Thought & Mini Rant…

Today, I ran across this article, and I found it interesting that many folks are discussing how “white hat hackers” could go about helping people by disclosing vulnerabilities before bad things happen. 

There are so many things wrong with this idea, I will just riff on a few here, but I am sure you have your own list….

First off, the idea of a corp of benevolent hackers combing the web for leaks and vulnerabilities is mostly fiction. It’s impractical in terms of scale, scope and legality at best. All 3 of those issues are immediate faults.

But, let’s assume that we have a group of folks doing that. They face a significant issue – what do they do when they discover a leak or vulnerability? For DECADES, the security and hacking communities have been debating and riffing on disclosure mechanisms and notifications. There remains NO SINGLE UNIFIED MECHANISM for this. For example, let’s say you find a vulnerability in a US retail web site. You can try to report it to the site owners (who may not be friendly and may try to prosecute you…), you can try to find a responsible CERT or ISAC for that vertical (who may also not be overly friendly or responsive…) or you can go public with the issue (which is really likely to be unfriendly and may lead to prosecution…). How exactly, do these honorable “white hat hackers” win in this scenario? What is their incentive? What if that web site is outside of the US, say in Thailand, how does the picture change? What if it is in the “dark web”, who exactly do they notify (not likely to be law enforcement, again given the history of unfriendly responses…) and how? What if it is a critical infrastructure site – like let’s say it is an exposed Russian nuclear materials storage center – how do they report and handle that? How can they be assured that the problem will be fixed and not leveraged for some nation-state activity before it is reported or mitigated? 

Sound complicated? IT IS… And, risky for most parties. Engaging in vulnerability hunting has it’s dangers and turning more folks loose on the Internet to hunt bugs and security issues also ups the risks for machines, companies and software already exposed to the Internet, since scan and probe traffic is likely to rise, and the skill sets of those hunting may not be commiserate with the complexity of the applications and deployments online. In other words, bad things may rise in frequency and severity, even as we seek to minimize them. Unintended consequences are certainly likely to emerge. This is a very complex system, so it is highly likely to be fragile in nature…

Another issue is the idea of “before bad things happen”. This is often a fallacy. Just because someone brings a vulnerability to you doesn’t mean they are the only ones who know about it. Proof of this? Many times during our penetration testing, we find severe vulnerabilities exposed to the Internet, and when we exploit them – someone else already has and the box has been pwned for a long long time before us. Usually, completely unknown to the owners of the systems and their monitoring tools. At best, “before bad things happen” is wishful thinking. At worst, it’s another chance for organizations, governments and law enforcement to shoot the messenger. 

Sadly, I don’t have the answers for these scenarios. But, I think it is fair for the community to discuss the questions. It’s not just Ashley Madison, it’s all of the past and future security issues out there. Someday, we are going to have to come up with some mechanism to make it easier for those who know of security issues. We also have to be very careful about calling for “white hat assistance” for the public at large. Like most things, we might simply be biting off more than we can chew… 

Got thoughts on this? Let me know. You can find me on Twitter at @lbhuston.

Ransomware

As many of you may have heard, businesses throughout the world have seen an increase in ransomware being used against them. What should businesses do to help prevent these sort of extortions from happening to them? This is what we will attempt to answer with this posting.

We have all heard the old adage “an ounce of prevention is worth a pound of cure”, nothing could be truer, especially for this particular situation! So lets go over some of the preventative steps that your organization may follow before you become infected with ransomware:

  • User education and training! Start off with end-user education, you know the people who are actually going to see these sort of attacks. Lets not focus on just select few like your sys-admins, but rather the entire organization. Everyone has a part in keeping your business secure and education is the key.
  • As part of the education of the end-users, let them know who to contact if they see something suspicious, whether that is your help desk or someone who is designated for your organization to help guide them through the process of what to do. The end-users have to be able recognize that something has occurred in order for them to report it in the first place.
  • Organizations should enforce the least privileged methodology. This is a way to grant the minimum amount of access to files as the person needs to perform their job-related duties. If a person does not need read/write access to certain files don’t grant it. This will help keep the ransomware from doing the same since they work based on the privileges of the person who is logged in at the time and encrypt files that the person has read/ write access to.
  • Most organizations now configure their email servers to prohibit them from sending or receiving executable files. Make sure yours does too. The real issue here are macros that are enabled when sent with a document. As this is a potential attack vector for this and other types of malware.
  • Patch your software to the most current version. By not doing so you may be leaving the door open for a variety of malware to take advantage of your company. The malware will exploit flaws in the older versions of software that your company uses. We have seen time and time again where businesses aren’t aggressively keeping their software updated to the latest version and they are targeted by threat actors as a result.
  • If possible restrict the execution of programs from temp folders in a user’s profile. For example, “c:\users\<username>\folder\temp”. What do I mean by this? If a virus or ransomware in this case, were to attempt to use a temp folder as the first execution point it would be blocked from being allowed to do so by Group Policy Objects. So you effectively nix the ransomware before it has had a chance to infect your computer!
  • Organizations should consider implementing some sort of web filtering such as keeping track of blacklisted IP addresses or domains.
  • Whatever antivirus solution your company employs please ensure that they are updated with the latest virus definitions to increase their effectiveness. A company could even consider having different antivirus products for different purposes, such as having one product for desktops and another for email. That way the company is ensuring that there is some degree of overlap in their antivirus coverage!
  • Adobe’s Flash should be disabled at this point, as it really has been a very popular infection vector for ransomware. Disabling it would greatly reduce the amount of infection vectors available to would-be attackers.
  • Lastly, backups are really the only way to restore functionality to the affected systems once they have been compromised, providing a backup process already exists in your organization and that the backups are checked for completeness. This way if you do need to use your backups, they will get you back on your feet as soon as possible with the least amount of downtime.

As always the education of all of your employees is key to this or any other sort of security related incident before it happens. As is effective communication both before a security incident starts and during the response/ recovery process.

Risks Inherent in Utilizing Economies of Scale

The number of people in the United States has been increasing heavily over time and we are currently the third most populace country on the planet. In the last century, the population has more than tripled here, and it is estimated that we will add more than 100,000,000 to the current total by 2050. One of the things that help us cope with such huge numbers is taking advantage of economies of scale.
For example, we build truly giant ships to carry our oil and cargo because the bigger the ship is the more hydrodynamic advantage there is and the less cost there is per ton for transportation. Similarly, we build enormous power plants and network them into grids because it is more efficient and cheaper per kilowatt hour to do so. There are many more examples of this trend all across American commerce. While this practice indeed does work and enables us in many ways, it comes with a variety of costs; one of which is increased risk.
We stand to lose a lot of oil and cause major environmental catastrophes if someone starts sinking major super tankers, for example. And if an enemy starts destroying our large power plants (or critical nodes in the infrastructure connecting them), the impact could be very much worse than that.
I mention all of this, because now we are seeing the trend toward economies of scale coming into the information processing world, mainly in the form of cloud computing. This trend is inevitable because it truly is more efficient, cheaper and improves peoples’ lives in many ways. But it must be realized that this centralization of data processing and storage brings with it the same increase in impact if a major compromise occurs – and the greater the impact, the greater the risk.
What this means in the information security world is that we need to have more security assurance built into these large cloud systems. It should be stated like a natural law: the bigger the system, the more effective the security controls need to be. So before you put all of your valuables into the cloud, keep the risks inherent in economies of scale in mind and vet your cloud provider’s security measures. Make sure that they have all the technical, operational, physical and management controls in place. Ensure that their information security program is transparent and reactive to realistic criticism. And ensure that your own organization realizes the risks inherent in the cloud and plans accordingly as well. Remember, it is your own organization that is ultimately responsible for the security of their data no matter where it is stored or processed.

Podcast Episode 7 Now Available

The newest version of the State of Security Podcast is now available. You can go the main page here, or listen by clicking on the embedded player below.

This episode features:

This episode is a great interview with Mark “Phork” Carey. We riff on the future of technology & infosec, how machine learning might impact security in the long term, what it was like to build the application-centric web with Sun, lessons learned from decades of hardware hacking and whole lot more! The short for this month is with @pophop, so check out what the self-proclaimed “elder geek” has to say as he spreads some wisdom. Let us know what you think and send in ideas for other folks you would like to hear on the podcast.