I think our software industry sometimes is blindsided when it comes to security. Don’t get me wrong, I am of course in favor of good security practices. But I think we could get better at understanding the trade-offs when improving security.

A story Link to heading

At a previous employer, we partnered with a big bank. They were using our SaaS’s REST API over the Internet. For security they used

  • TLS for encryption to make sure no one was eavesdropping over the Internet.
  • a static API token to authorize with us.
  • certificate pinning to make sure they were talking to us over the Internet (and not Eve-the-evil-hacker).

The CISO department of this particular bank reached out to us and required us to to use Mutual TLS (mTLS) since it was “more secure”. I thought their request was security theatre; it would not improve our security in any particular way. Also, we had used TLS+pinning+token for many years, it worked well, had good processes in place for this, and knew how it worked.

Ever tried to argue against a bank? I tried to explain that we already covered all their actual requirements:

  • No one could eavesdrop.
  • We knew they were the ones making API calls to us.
  • They knew they were making API calls to us and not someone else.

Further, I knew that mTLS would require authentication on a different network layer. It would add more technical complexity for us. Also, we did not want to become a CA and start doing complicated CSRs. Still, the customer keps pushing for this.

The pushback felt hopeless, but one day I had a breakthrough! I explained to the customer that their solution had “operational risk”, particularly around certificate expiration and renewal. The term “operational risk” was like a magic password that opened up new doors in the conversation. The CISO representative responded with:

“Oh, operational risk you say? That makes a lot of sense. Our department not only works with security but with all types of risks. We weigh different types of risks against each other. We will consider your operational risk!”

With that, I never heard from them again. I won my argument!

My biggest learning from this was how useful it is for a security department to take a more holistic approach to risk. Without this, you are missing what you are trading for “higher security”.

Other types of risk Link to heading

Here are some examples of “operational risk” that I have seen/heard being down-prioritized at various companies:

  • Systems stability. My example above is a good example of this. We risked downtime if certificates would expire.
  • Reduced speed of development. For some companies, innovation might be more important than security.
  • Human error. Certain security controls add more manual work and increases the risk of making mistakes.
  • Cost increases. There are plenty of SaaS and AWS services to improve security, but they add costs. If you are a company low on budget, enabling every security service out there will add costs. Not to mention that the salary for engineers implementing security controls also is a thing.

The above list is likely not exhaustive.

Closing thoughts Link to heading

I have heard people refer to companies as having “an unhealthy security culture” if they don’t have the right controls in place. Similarly, I would say that companies that focus too much on security can have an unhealthy security culture.

It’s okay to say no to adding additional security control. My personal approach to security is to take an iterative approach, focusing on the highest security risks, but weighing the controls against other types of risk.