DLP 101: How to Prevent Data Exfiltration in the Cloud

These days, your organization's data is its most valuable asset. But what happens when that data slips through your fingers?

Picture this: It's Friday afternoon, and your security team receives an alert about an unusual number of downloads from your cloud storage app, Google Drive. As you investigate, you realize it's corporate IP that's being downloaded en masse by a departing employee.

This type of exfiltration incident isn't just hypothetical; it's a reality that organizations face on the daily.

What is cloud data exfiltration?

Think of cloud data exfiltration as the unauthorized transfer of sensitive data from your cloud environment to an external location, like an external device or unsanctioned cloud app. Data exfiltration isn't always a dramatic event; sometimes, it's a slow, steady trickle of data that can go unnoticed for months.

So, what kind of data is at stake in these exfiltration scenarios? Pretty much everything under the sun, including:

Corporate IP, such as source code or trade secrets
Sales data, like books of business
Customer data, including PII and PCI like social security numbers or credit card numbers
Secrets like login credentials, API keys, and cryptographic keys

These aren't just abstract concepts. They're the core of your business operations, customer trust, and competitive edge.

For instance, consider the 2024 Disney breach, in which a hacker group leaked over 1TB of data from Disney's Slack environment. This data spanned messages from over 10,000 Slack channels including "upcoming project details, financial information, information technology information, and other confidential information."

Why is exfiltration a growing concern?

You might wonder, "Why are exfiltration threats becoming more common?" The answer lies in the nature of cloud computing and how we work today.

The collaboration conundrum

Cloud apps like Slack, Google Drive, and Salesforce make remote collaboration easier than ever. However, such frictionless communication can inadvertently lead to unintentional insider threats. Imagine an employee copying and pasting IP, or using a personal cloud account for work files. These daily occurances—and more—can create pathways for sensitive data exfiltration.

Everyday misconfigurations

Cloud infrastructure misconfigurations represent one of the most common data exfiltration risks. It's as simple as an employee accidentally setting a file's permissions to "Share with anyone with the link" or storing sensitive files in a public folder. These human errors create opportunities for malicious actors to access and exfiltrate data.

Spotty visibility

As the classic cybersecurity adage goes, "You can't secure what you can't see." Lack of visibility into exfiltration events (like file transfers or downloads) is a major blank spot for many organizations. By the time you notice unusual activity, it may be too late to act on it.

What are the consequences of data exfiltration?

When data exfiltration occurs, the impacts can cause a myriad of issues such as:

Operational disruptions: If your team needs to investigate and contain a breach, it may interrupt workflows across the organization.
Compliance issues: Depending on the data involved, you might face regulatory scrutiny and costly fines.
Customer trust: Even small data leaks can cause reputational damage and erode customer confidence if not handled properly.
Financial impact: From investigation costs to lost business, the financial implications of a data breach can add up quickly.

For growing companies, these issues can be particularly challenging, as they can affect investor confidence.

What's worse: External threats or insider threats?

While external threats are a concern, don't overlook the risks from within your organization. Insider threats, both accidental and intentional, pose significant risks to your data security.

The accidental insider

Not all data breaches result from malicious intent. Often, well-meaning employees unintentionally expose sensitive information while completing day-to-day tasks. Common scenarios include:

Overly permissive sharing settings: An employee might share a Google Drive folder with “Anyone with the link” instead of specific individuals.
Uploading sensitive files to personal accounts: An employee could upload confidential documents to their personal Google Drive account or mobile device.
Accidental sharing with former employees: An employee might forget to remove shared permissions in Google Drive, allowing former employees to access and misuse sensitive data.

These exfiltration scenarios highlight the importance of ongoing security awareness training and robust security controls.

The intentional threat actor

While less common, intentional insider threats can be more damaging. This might involve:

A disgruntled employee downloading confidential files to a personal device
A departing worker sharing trade secrets with a new employer for financial gain
An individual with a grudge deliberately misconfiguring systems to allow unauthorized access

To mitigate these risks, it's best to implement robust user activity monitoring, strong access controls, and go-to offboarding procedures.

What are common techniques used by threat actors?

To defend against data exfiltration, you need to understand the tactics used by malicious actors. Here are some common exfiltration techniques:

Credential theft

Stolen login credentials are a primary vector for unauthorized access. With valid credentials, bad actors can often bypass security controls and exfiltrate data without raising immediate alarms. Protect your organization by:

Implementing multi-factor authentication (MFA)
Avoiding easy-to-guess passwords, or generating complex passwords with a password manager
Regularly auditing user accounts and access privileges

Malware and persistent threats

Sophisticated malware can establish backdoors in your cloud applications and corporate networks. These persistent threats allow for ongoing data exfiltration. Counter this by:

Keeping all corporate devices and software up to date
Onboarding a robust endpoint security solution
Conducting regular vulnerability assessments

Social engineering attacks

Why break through technical defenses when you can trick someone into letting you in? Social engineering attacks, including phishing attacks, remain a top vector for data exfiltration. Protect your organization by:

Providing regular security awareness training
Implementing email filtering solutions
Establishing clear protocols for verifying identities before sharing sensitive information

How does the shared security model fit into all this?

Cloud providers offer robust security measures, but they're not responsible for your data. The shared responsibility model delineates where the cloud provider's security responsibilities end and where yours begin.

Your cloud provider typically handles:

Physical access to data centers
Network infrastructure security

Meanwhile, you're responsible for:

Classifying and protecting sensitive data
Monitoring for suspicious activities and potential threats
Managing identity and access controls

Remember, while cloud services provide powerful tools, it's up to you to use them effectively to prevent unauthorized data transfers and exfiltration attempts.

What are best practices for securing your cloud environment?

Now that we've explored the threat landscape, let's discuss practical solutions. Read on for our top tips for fortifying your cloud apps.

1. Minimize data sprawl

In short, data sprawl increases your attack surface. The more places your sensitive data resides, the higher the risk of exfiltration. Take these steps to stop data sprawl in its tracks:

Implement cloud data loss prevention tools, or cloud DLP tools, to discover where your sensitive information lives
Consolidate data storage where possible
Regularly purge unnecessary data

2. Implement strong access controls

Think of access controls as your first line of defense. They determine who can access your data and what they can do with it. Here's how to tighten your access controls:

Enforce the principle of least privilege
Implement multi-factor authentication across all user accounts
Regularly audit and revoke unnecessary access rights

3. Educate and train employees

Your employees can be your strongest asset in preventing accidental insider threats. Invite them to be a stakeholder in their own company security by doing the following:

Conduct regular, engaging security awareness training
Use simulated exercises to test and reinforce learning
Offer automated coaching for when employees accidentally violate security policies

4. Leverage advanced cloud data loss prevention solutions

Cloud access security brokers (CASBs) and legacy DLP tools often struggle in cloud environments; they generate too many security alerts and can't keep up with the dynamic nature of cloud data. Instead, look for next-gen DLP solutions that offer:

AI-powered detection for enhanced accuracy
Context-aware policies that can adapt to evolving threats over time
Data security posture management capabilities, including user behavior monitoring

5. Adopt a data-centric security approach

Instead of focusing solely on perimeter defense, shift your strategy to protect the data itself. This approach involves:

Data classification and tagging
Encryption of sensitive data both at rest and in transit
Permissions management to control how information is used and shared

6. Implement continuous monitoring

Cyber threats don't follow a 9-to-5 schedule, and neither should your security measures. Set up continuous, automated monitoring to:

Detect unusual activity in real time
Identify potential exfiltration attempts before data leaves your environment
Provide a comprehensive audit trail for investigations and compliance

7. Develop and test an incident response plan

Hope for the best, but prepare for the worst. A well-crafted incident response plan can make the difference between a minor hiccup and a major security breach. Your plan should:

Define clear roles and responsibilities
Establish communication protocols
Include steps for containment, eradication, and recovery
Be regularly tested through tabletop exercises and simulations

How does Nightfall enhance your data exfiltration prevention strategy?

While the strategies we've discussed form a solid foundation for data protection, many organizations find that they need additional tools to truly secure their cloud environments. This is where Nightfall comes in.

Nightfall is an AI-native cloud DLP platform that was designed to address the unique challenges of protecting data in modern cloud environments. Here's how Nightfall can bolster your defenses against data exfiltration:

Advanced data discovery: Nightfall uses generative AI (GenAI) and machine learning (ML) to automatically discover, classify, and protect sensitive data across your cloud applications. This addresses the data sprawl issue by giving you visibility into where your sensitive information resides.
Real-time monitoring: Nightfall continuously monitors data movement across your cloud applications, allowing for the detection of potential exfiltration attempts as they happen.
Contextual analysis: Unlike traditional DLP solutions, Nightfall understands the context in which data is being used. This reduces false positives and allows for more accurate detection of truly risky behavior.
Automated remediation: When a potential data exfiltration attempt is detected, Nightfall can automatically take action, such as quarantining files or revoking user access, to prevent data loss.
Integration with cloud services: Nightfall seamlessly integrates with popular cloud services like Google Cloud and Microsoft 365 to offer protection across your entire cloud ecosystem.

How does Nightfall make security teams' lives easier?

Nightfall doesn't just protect your data; it also helps security teams to sleep soundly at night thanks to:

Reduced alert fatigue: By using contextual analysis, Nightfall significantly reduces false positives, allowing your security team to confidently automate workflows like triage, investigation, remediation, and coaching.
Centralized management: Nightfall provides a single dashboard for managing data protection across multiple cloud services. Prefer to get alerts to your platform of choice? Nightfall's got you covered with automated alerts for Slack, Teams, Jira, email, or webhooks.
Compliance support: Nightfall helps organizations meet compliance requirements for HIPAA, PCI-DSS, SOC 2, and beyond by providing detailed audit logs and reports on data access and movement.
Customizable policies: Security teams can easily create and enforce custom data protection policies tailored to their organization's specific needs.
Continuous improvement: Nightfall's AI detection engine continuously improves based on your organization's data, becoming more accurate over time in detecting potential threats.

What does it mean to embrace a holistic approach to cloud security?

Securing your cloud environment against data exfiltration isn't a one-time task—it's an ongoing process. As threats evolve, so must your defenses. But technology alone isn't enough. You need to foster a security-first culture within your organization.

Encourage everyone, from the C-suite to the newest intern, to think about security in their daily activities. Make it a part of your company's DNA. When security becomes second nature, you create a human firewall that complements your technical defenses.

Safeguarding your data, securing your future

The threat of data exfiltration in the cloud is real, but it's not insurmountable. By understanding the risks, implementing robust security practices, and leveraging advanced tools like Nightfall, you can protect your organization's most valuable asset—its data.

The cloud offers incredible opportunities for growth and innovation. Don't let the fear of data exfiltration hold you back. Instead, use it as motivation to build a stronger, more resilient security posture. Your future self—and your customers—will thank you.

Are you ready to take your cloud security to the next level? The time to act is now. Get in touch with the Nightfall team for your own custom demo today.

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