I'm Running Canaries, but...

...what if someone finds out?

Do attackers care if there are canaries in my network?

People wonder if they need to hide the defensive tech used on their networks. Like all interesting dilemmas, the answer is nuanced.


In defense of obscurity

In any discussion about obscurity you will almost certainly have someone shout about “security through obscurity” being bad. As a security strategy, obscurity is a terrible plan. As an opportunity to slow down or confuse attackers, it’s an easy win. Every bit of information an attacker has to gather during a campaign gains the defender time.

This is very much a race against time. No breach happens the moment a shell is popped or SQL injection is discovered. Attackers are flying blind and must explore the environments they’ve broken into to find their target. Defenders can seize the opportunity to stop an incident before it becomes a breach.

It is often true that attackers typically operate with a fuller view of the chessboard than defenders. However, when environments are running with defaults, they meet attackers' expectations. Defenders who are able to introduce unexpected defenses or tripwires to this chessboard can turn this asymmetry to their advantage.


What are defenders so afraid of?

Defenders tend to be concerned that their security products:
1. could, themselves, be insecure
2. may not work as expected when attacked
3. could possibly be evaded if attackers are aware of them
4. will simply eat labor without producing much value

Pardon the pun, but this isn’t a very defensible position to be in.

We know very well from Tavis Ormandy, Joxean Koret, Veracode, and others that security software and products are notoriously insecure. According to Veracode, in fact, they come in next-to-last place.


If that’s not discouraging enough, the average security product is difficult to configure, challenging to use and requires significant resources to run and maintain. There is no shortage of reasons for wanting to hide the details of security products in use.

The Importance of Resilience

Let’s consider the flipside for a moment: offensive tools and capabilities. There’s a solid argument for keeping offensive capabilities secret. For example, the zero-day vulnerabilities used by Stuxnet wouldn’t have been as effective if they had been previously reported and patched. For some time, military aircraft have had advantages because details of their capabilities or even their very existence were closely guarded secrets.

Defenses are a very different case, however. These must stand the test of time. They are often visible to outsiders and similar to defenses used by other organizations. Vendors, after all, will advertise their products in order to sell them. Defenses need to hold up under close scrutiny and be robust enough to last for years without needing to be replaced. The argument for keeping them secret could perhaps slow down an attacker but not by an appreciable amount. 

Ultimately, defenses need to work regardless of whether attackers are aware of their presence.

Attackers Discover Your Secret: Canaries

It’s okay - we’ve planned for this moment. We spent significant effort ensuring Canaries are unlikely to ever be the ‘low hanging fruit’ on any network. We’ve also made architecture choices that minimize blast radius should a Canary ever be exploited (e.g. we won’t span VLANs, ever). In short, compromising a Canary would be very difficult and will never improve an attacker’s position.

With a direct attack against a Canary unlikely to prove useful, let’s look at the attacker’s remaining options.

Scenario 1: The attacker has no idea you’ve deployed Canaries and Canarytokens. Since they’re not expecting honeypots, they’re less concerned with being noisy. They’re likely to trip alerts all over the place, as they run scans and attempt to log into interesting-looking devices.

Scenario 2: The attacker knows you use Canaries, but they’re flying blind. Even though they know honeypots are in use, they don’t know which are real and which are fake. This presents them with a dilemma - being sneaky is a lot more work, but they still need some way of exploring the network without triggering alerts. It’s likely to be in the attacker’s best interest to find a different target.


An unexpected bonus we never planned for is that Canaries are super scalable. Many customers start with five or ten and grow to dozens or hundreds. Stepping back into the attacker’s shoes - are you on a network with five or five hundred? Has this organization deployed a hundred Canarytokens or a million?

Conclusion

The underlying principle is a shift in thinking. Defeatist phrases like, “it’s not a matter of if, but when you get breached” have discouraged defenders. The reality is that the attacker is typically coming in blind, while the defender has control over the environment. By setting traps and tripwires, the defender can tip the outcome in their favor.

We think it’s a very positive and empowering change for the defender mindset. It’s your network - own it and rig the game.



1 comment :

  1. Using the Canary Islands as bait can be quite an effective way of protection. The attackers will certainly be attracted to this system.

    ReplyDelete