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Business Continuity is concerned with information security risks and impacts

2015-08-02 by lucaskauffman. 0 comments

A Business Continuity Programme (BCP) is primarily concerned with those business functions and operations that are critically important to achieve the organization’s operational objectives. It seeks to reduce the impact of a disaster condition before the condition occurs. Buy-in from top level management is required as a review is required of each function defined in the business as to ensure all key-personnel is identified. Why would a business require a BCP?

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The BCP ensures the business can continue in case of (un)foreseen circumstances. To motivate top-level management to support the BCP, the best way is to set up a risk/reward overview and use examples to show what can happen when you do not have a BCP in place. The most important question to ask is: “If we (partially) shut down the business for x amount of time, how much money would this cost, both short (direct business loss) and long term (indirect business loss from reputational damages)?”. Losing critical systems, processes or data because of an interruption in the business could send an organization into a financial tailspin.

The main concern of a BCP is to ensure availability of the business is maintained. Confidentiality and integrity should also be addressed within the Business Continuity Plan. In terms of availability the risk to business continuity is often explained as a service interruption on a critical system, e.g. a payment gateway of a bank goes down, preventing transactions from occurring. The short- and long-term impact are financial losses due to the bank not being able to process transactions, but also clients becoming more and more dissatisfied. Confidentiality in BCP could for example be the transfer of personal data during a disaster recovery. An objective of disaster recovery is to minimize risk to the organization during recovery. There should be a baseline set of documented access controls to use during recovery activities. They are necessary to prevent intrusions and data breaches during the recovery. The impact here can be one of reputation but also of financial nature. If a competing company can for example obtain a set of investment strategies, it could assist the competing company to invest against them, resulting in significant financial losses and even bankruptcy.

Integrity of information means that it is accurate and reliable and has not been tampered with by an unauthorized party. For example it is important that the integrity of each customer’s data, but also information originating from third parties, can be ensured. An example of the impact of integrity violation: when a bank cannot rely on the integrity of data, for instance if it authorizes transactions to a nation or person on a sanctions list (originating from a third party), they could be heavily fined, but also might lose their banking license. A BCP goes wider than just impacts, it also addresses risks. A business impact analysis is performed to understand which business processes are important. These “critical” business processes are provided with special protection in the framework of business continuity management, and precautions are taken in case of a crisis. “Critical” in the sense of business continuity management means “time-critical”, which means that this process must be restored to operation faster because otherwise a high amount of damage to the organisation can be expected. While the BIA answers the question of what effects the failure of a process will have on the organisation, it is necessary to know what the possible causes of the failure could be. Risks at process level as well as risks resource level need to be examined. A risk at the process level could be the failure of one or more (critical) resources, for example. A risk analysis at the resource level only looks for the possible causes of the failure of these critical resources.

BCP relies on both impact and risk assessments, but making a risk assessment without an impact assessment is difficult. ISO 22301 requires a risk assessment process to be present. The goal of this requirement is to establish, implement, and maintain a formal documented risk assessment process that systematically identifies, analyses, and evaluates the risk of disruptive incidents to the organization.

I want to conclude with stating that risk analysis and business impact analysis (BIA) are cornerstones in understanding the threats, vulnerabilities and mission-critical functions of the organization and are thus required if one wants to discover the business’s critical processes and make a correct prioritization.

A short statement on the Heartbleed problem and its impact on common Internet users.

2014-04-11 by lucaskauffman. 2 comments

On the 7th of April 2014 a team of security engineers (Riku, Antti and Matti) at Codenomicon and Neel Mehta of Google Security published information on a security issue in OpenSSL. OpenSSL is a piece of software used in the encryption process; it helps you in coding your computer traffic to ensure unauthorized people cannot understand what you are sending from one computer network to another. It is used in many applications: for example if you use on-line banking websites, code such as OpenSSL helps to ensure that your PIN code remains secret.

The information that was released caused great turmoil in the security community, and many panic buttons were pressed because of the wide-spread use of OpenSSL. If you are using a computer and the Internet you might be impacted: people at home just as much as major corporations. OpenSSL is used for example in web, e-mail and VPN servers and even in some security appliances. However, the fact that you have been impacted does not mean you can no longer use your PC or any of its applications. You may be a little more vulnerable, but the end of the world may still be further than you think. First of all some media reported on the “Heartbleed virus”. Heartbleed is in fact not a virus at all. You cannot be infected with it and you cannot protect against being infected. Instead it is an error in the computer programming code for specific OpenSSL versions (not all) which a hacker could potentially use to obtain  information from the server (which could possibly include passwords and encryption keys, along with other random data in the server’s memory) potentially allowing him to break into a system or account.

Luckily, most applications in which OpenSSL is used, rely on more security measures than only OpenSSL. Most banks for instance continuously work to remain abreast of security issues, and have implemented several measures that lower the risk this vulnerability poses. An example of such a protective measure is transaction signing with an off-line card reader or other forms of two –factor authentication. Typically exploiting the vulnerability on its own will not allow an attacker post fraudulent transactions if you are using two-factor authentication or an offline token generator for transaction signing.

So in summary, does the Heartbleed vulnerability affect end-users? Yes, but not dramatically. A lot of the risk to the end-users can be lowered by following common-sense security principles:

  • Regularly change your on-line passwords (as soon as the websites you use let you know they have updated their software, this is worthwhile, but it should be part of your regular activity)
  • Ideally, do not use the same password for two on-line websites or applications
  • Keep the software on your computer up-to-date.
  • Do not perform on-line transactions on a public network (e.g. WiFi hotspots in an airport). Anyone could be trying to listen in.

Security Stack Exchange has a wide range of questions on Heartbleed ranging from detail on how it works to how to explain it to non-technical friends. 

Authors: Ben Van Erck, Lucas Kauffman

About Secure Password Hashing

2013-09-13 by lucaskauffman. 5 comments

An often overlooked and misunderstood concept in application development is the one involving secure hashing of passwords. We have evolved from plain text password storage, to hashing a password, to appending salts and now even this is not considered adequate anymore. In this post I will discuss what hashing is, what salts and peppers are and which algorithms are to be used and which are to be avoided. more »

WiFi security: history of insecurities in WEP, WPA and WPA2

2013-08-28 by lucaskauffman. 0 comments

Recently I answered a question on security.stackexchange.com regarding security in wireless protocols. The OP wanted to know more about what methods were available to break into a wireless network and how long it would take.

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About the recent DNS Amplification Attack against Spamhaus: Countermeasures and Mitigation

2013-04-15 by lucaskauffman. 1 comments

A few weeks ago the anti-spam provider Spamhaus was hit by one of the biggest denial of service attacks ever seen, producing over 300 gbit in traffic. The technique used to generate most of the traffic was DNS Amplification, a technique which doesn’t require thousands of infected hosts, but exploits misconfigured DNS servers and a serious design flaw in DNS. We will discuss how this works, what it abuses and how Spamhaus was capable of mitigating the attack.

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Exploiting ATMs: a quick overview of recent hacks

2012-08-10 by lucaskauffman. 0 comments

A few weeks ago, Kyle Rozendo asked a question on the IT Security StackExchange about Cracking a PCI terminal using a trojan based on the card. It caught my attention, so I started digging a little deeper into this matter.

There are some difficulties involved in hacking an ATM:

  • Often proprietary software
  • Often custom OS or modified embedded Windows

This means a high level of understanding is necessary, as well as access to ATMs to test on. All of the attacks I’ve dug up had some level of inside information before they were constructed.

2009: Diebold gets targeted by Skimer-A Trojan

One of the first serious hacks I came by was a Trojan found in ATMs in eastern Europe around 2009. As reported by Sophos, the attack was aimed at Diebold Opteva ATMs.

The Trojan was named Skimer-A. It’s main goals were:

  • Steal information (card numbers and PINs)
  • Allow remote access
  • Drop more malware

The hack required physical access to the machine. The perpetrators used social engineering, to persuade stores to allow them physical access to the machine after hours, so they could install the virus. After an analysis of the malware, Diebold concluded the attackers also had to have inside information about the systems. A lot of the functions used to extract information were part of the ATMs operation software, but were never documented. They also knew administrative passwords and unlocked the custom Windows CE version Diebold used as well as misconfiguring its firewall. (This was concluded from the security update by Diebold.)

2010: ATM Jackpotting by Barnaby Jack

In 2010, McAfee security expert, Barnaby Jack presented his “ATM Jackpotting” at Blackhat. He was able, after careful analysis with physical access to a few teller machines, to write a tool that could remotely exploit an ATM and patch it so you can call a custom menu with an access code or remotely start emptying the ATM’s money cassettes (hence Jackpotting).

The attack is aimed at standalone and hole-in-the-wall ATMs. The ATMs often run:

  • ARM/XSCALE processor
  • Windows CE
  • TCP/IP, Dial Up or CDMA wireless
  • Support for SSL
  • 3DES encrypted pin pad

In his research he used 3 different ATMs (he ordered these and got them delivered at home). He started his research by looking at the internal workings and, although there were some security measures in place, once a he had physical access many possibilities started to appear. He started by looking for a way to modify the boot sequence, because the ATM boots into its proprietary software. This means he has to patch the system so he can get access to a shell. He accomplished this by using a JTAG debugger.

Using the JTAG module, he was able to send a break when starting the difference services. After this he could launch a proper shell.

This work was all necessary to reverse engineer the software and develop the actual attacks:

  • Walk up attack by “upgrading” the firmware with a flashcard (this required physical access, and a key to open the machine and access the motherboard – such keys are standard, and easy to find on the Internet).
  • Remote configuration attack, firmware can be upgraded remotely

The latter is the most interesting attack, but there are some security defenses in place that make a bruteforce attack impossible. However Barnaby Jack was able to find a vulnerability in the authentication mechanism which allowed him to log in to the machine. He wrote a tool to do these attacks, named “Dillinger”. Now the problem he faced was how to find the ATMs on the internet.

Whilst ATMs support TCP/IP, about 95% of all ATMs still connect to the internet using Dial Up. This means War Dialing using a VOIP tool like WarVox, makes it possible to go and find ATMs on the net. Most of the ATMs use a proprietary protocol, so once you identify this protocol you know an ATM is listening on the other side and you can go and try to exploit it. Once you have access to the ATM you can spawn a shell and install a rootkit. You will still need to identify where the ATM is physically located so you can go and collect the money. This is done by reading the configuration file (often the address is present on the receipts).

The rootkit to keep access to the teller is called “Scrooge”. It hides itself on the machine. One difficulty is that the kit needs to be modified for almost every version of ATM software that’s running because of different peripherals and non-standard ways to communicate. After installing the kit you can walk up to the ATM and enter a keys equence on the keypad, this brings up a custom menu that allows you to jackpot the ATM (completely empty it) or give you a specific amount of cash. This can also be done remotely.

Barnaby suggests following countermeasures:

  • Better physical locks
  • Executable signing at the kernel level
  • Implement Trusted Environment
  • Put them on a seperate, firewalled network
  • Disable the Remote Management System if you aren’t using it
  • More and better code auditing

You can find the complete presentation on Vimeo.

2012: MWR InfoSecurity reveals chip and PIN vulnerability

Chip and PIN is a system where one can insert his banking or credit card into a small machine and make an electronic payment. In the U.K. there is a government backed initiative to make these as widespread as possible. MWR InfoSecurity, a Basingstoke (U.K.) based security company, revealed a way to attack these terminals with a custom PIN card. The attacks demonstrated at Blackhat 2012:

  • Producing a fake receipt, making a cashier think the payment was successful
  • Infect PIN entry devices to collect card data and harvest these with another rogue card
  • Network and interface attack

Apparently the exploits involved were present in normal computers more than a decade ago, making you wonder why this problem was ignored or went undetected. Especially when Cambridge University researchers warned banks of the lack of security in these type of machines as early as 2010. Issues included unencrypted and unauthenticated communication between terminal and remote administration server, which makes a man in the middle attack dead easy. At the moment of writing there hasn’t appeared any white paper (I’m aware of or had access to). The devices affected were produced by VeriFone.

Conclusion

If we look at the attacks over time, it becomes clear that they can be deployed faster and faster. The hacks still require a high level of knowledge and understanding of these systems, but because there are some really basic security issues like bad code reviewing, unencrypted/unauthenticated communication and bad physical security, the attacks are seemingly easy to deploy. It’s up to the producers of these machines to start securing them. Companies still rely too much on security through obscurity and do not expect an attack because a hacker would need insider information. Previous articles suggest that it’s not extremely hard to get that information.

Sources:

Tor: Exploiting the weakest link

2012-04-10 by lucaskauffman. 5 comments

Since the birth of the internet, there has been censorship. People have always been looking for ways to anonymously access the internet, either by proxy or VPN, however these still (can) log traffic origin and destination.

Since a few years there have been a few projects to anonymize traffic. One of the more famous ones is Tor (The Onion Router).

How Tor works

Tor uses servers and clients. When you request a webpage from your client, Tor will make an encrypted request to a randomly selected relay server called an Onion router. This Onion router knows who you are. Next thing the router does is ask another Onion router to relay the message. This second Onion router only knows the first Onion router. The second asks a third, the third asks the fourth, etc. No single router knows the complete route, however the client does.

The client can access a database which holds all the relays and if he wants, he can select his own route or a random route is selected. He then gets all the public keys for the route and encrypts his message in reverse order, starting with the public key of the last node, than the one to last node, etc. So the encryption is layered (just like the layers of an onion). However there is also a message for every node that contains the next hop. Now at the exit router the message is decrypted completely and the request for the webpage is made. For the webserver that serves the question, the client’s IP is the IP of the exit node.

The weakest link

So traffic is encrypted multiple times and relayed through different servers. This ensures anonymity. However… everyone can set up a Tor exit node … and everyone that has an exit node, can monitor the traffic.

The weakness in this technology is one we find in other technologies as well, the so called “user”.

A lot of people are concerned about their anonymity and figure they are safe when using Tor. They forget that when using a physical line or an encrypted Wifi AP, The chances of getting a Man in the Middle Attack (MMA) is small.

Now because we can easily host an exit node, we can sniff traffic from people who think they are anonymous, a lot of people in fact. At 20 Mbit (the max speed we allowed Tor to use), we got about 200 different Facebook sessions a day.

Facebook

Users forget about certain things, like facebook over https. I’ve heard people say “I’ve enabled https on my facebook account, so when I log in, I’m safe.” Well that’s good for them but they forget that often, if you do not explicitly state https for the facebook login page, your password and username is sent PLAIN TEXT over the internet. Facebook doesn’t know you want a secure line before you are logged in.Obviously this goes up for a lot of different sites other than Facebook.

The whole point of Tor is to be anonymous, but users get facebook accounts with often their full name and address on it, and then log in insecurelly.

One could write a script (and we made a proof of concept), that looks for usernames and passwords or hijacks sessions and automatically goes to a facebook like page “I am using Tor to be anonymous”.

I am not saying Tor is unsafe, all we wanted to proof is that people need to think twice before thinking they are anonymous and safe on the internet. There will always be people that want to do malicious stuff. We could have hijacked about 20 accounts in half an hour and revealed people who use Tor or get into their emailboxes. (like Dan Egerstad also prooved in 2007).

Youtube Video

The comments in the clip are in Dutch, but basically we set up a tor node and used tshark to capture traffic. We specified we were interested in http traffic coming/going from Facebook. We then took the session cookie and injected it into our browser which then automatically logs us into Facebook as that user.

Conclusion

Tor is a good anonymity provider, but like all tools, you need to use it in the correct way.