Your data was stolen - now what?

Issue 2/3 2023 Information Security

How would you know if someone breached your organisation's systems and stole data? Ideally, you would catch the culprits in the act or (less ideally) they would contact you demanding payment.

But you might only discover the theft when your stolen data surfaces publicly. Even major international companies were unaware of a breach until their stolen data surfaced on online trading forums. Just last year, a routine scan of a known illicit data marketplace uncovered a database of 1.2 million credit and debit card details.

These so-called darknet markets are very lucrative—a recent report from the Universities of South Florida and Georgia State estimates that data trading on 30 darknet markets made over $140 million in just eight months.

Discovering your business data on such a market suggests that your systems were breached a while ago, and the perpetrators might still be active. What are the proper steps for taking action?

"Companies must be careful when they respond to stolen data found online," says Gerhard Swart, CTO at cybersecurity company, Performanta. "They might have a knee jerk reaction, such as trying to buy their data back or threaten the market with legal action. But those actions can cause more damage.”

Swart recommends companies take a four-step approach when dealing with a data breach.

Step one: Start your incident response plan

Every business should have a tested incident response plan that guides the situation. This plan will stipulate appropriate actions, activate a response team and allocate their responsibilities.

"Your incident response plan is your blueprint for a breach situation. It should guide you on the first steps, which include notifying your cybersecurity provider and legal team, and forming a predetermined response team. It will also advise whether to disconnect systems or shut them down. You should develop an incident response plan, ideally in collaboration with an experienced security provider. Having a plan makes an enormous difference," says Swart.

Step two: Verify the data is real

Criminals are not above scamming others by offering fake data. It's important to verify claims of stolen data. Work with your data experts and security partners to determine whether the data is genuine. They can source samples of the data and check it against your inventory.

"When you find data allegedly from your organisation, check if it's real. If it's yours, you have a breach situation and can focus on determining the data's origin. This is a delicate process. Engaging with online criminals could put you in hot water with the law. Use professionals with the right technical and legal experience,” says Swart.

Step three: Notify regulators

In tandem with the above steps and your legal team's support, you must notify regulators. Not doing so promptly or trying to hide evidence of a breach can lead to serious problems, including penalties and jail time.

"Your legal team should advise you on your options and responsibilities, including the procedure and timeline to notify regulators. For example, the Protection of Personal Information Act requires immediate notification if personal data is involved. If you conduct business in other jurisdictions or have impacted systems located there, you may also have to notify them. Do not try to cover the breach up. Security people have been prosecuted for doing that,” says Swart.

Step four: Secure your operations

Few data breaches are quick. In most cases, the attackers would have spent time exploring the business' systems, gathering credentials, planting malicious tools and creating backdoors. Consider taking impacted machines offline (but keep them running for forensics purposes) and lock down physical areas that give access to affected systems.

"You want to limit the damage. But if you start unplugging things in a panic, you could harm investigations. Liaise with security partners and law enforcement to determine when to resume those systems. Your incident response plan should cover these choices. Also closely monitor entry and exit points. Reset credentials and limit the number of accounts with access, since the criminals likely created special accounts. If possible, you should replace affected systems with clean machines," says Swart.

Unfortunately, your business data appearing online means the horse has already bolted from the stable. Trying to negotiate with the data thieves is not recommended without the help of professionals skilled in such matters. Threatening legal action against criminals or marketplaces will have little effect and may even backfire. Attempting to get the data deleted is unlikely to be effective since you don't know if other copies exist.

Prevention is better than cure. Use proactive security to prevent and limit attacks and notify you early of breach attempts. Run enhanced identity management and audits to catch criminals trying to access and duplicate permissions. Check configurations of high-value targets, such as Active Directory servers. And create data backups – the only thing worse than discovering your data online is losing access to that data.




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