Cyberattacks and data breaches can’t be completely stopped in a day. As technology grows, attackers find different ways to intrude, constantly adapting to new security measures. Gartner forecasts that by 2027, generative AI will play a role in 17% of all cyberattacks, highlighting the growing threat of AI-driven tactics in the evolving landscape of cybersecurity. So, companies should always get ready to cope with any kind of sophisticated attacks at any time.
But what if you cannot defend because the attackers have already intruded into your system and a data breach occurs?
Let’s discuss the 5-step best practices for a business after a data breach occurs in detail.
Steps to Take After a Data Breach
Step 1: Understand the Breach
The first 72 hours matter a lot in data breach response and incident detection. Security breaches are not very apparent in the systems in the beginning. It can be an unusual activity or alerts from systems like SIEM, network monitoring tools, or external sources (e.g., law enforcement agencies or trading partners).
So, begin by answering these questions:
- Is this a security incident?
- What sensitive information might be at risk?
- What is the best way to respond?
- Suggested Reading: Using Metadata for Incident Response to Strengthen Your Security Strategy
The Common Mistake in Response:
The mistake that the security team often makes is taking immediate action to fix the issue (e.g., taking systems offline), which is a typical reaction even before understanding the attack. This can make the situation worse and cause more damage than the attacker caused.
First, understand the breach and contain it, ensuring no further escalation or damage, because:
- Attackers can quickly escalate their access and cover their tracks.
- Valuable evidence (like logs or endpoint artifacts) can be overwritten or deleted.
The quicker you act, the less damage the breach will cause. Identifying the incident type helps you respond properly and reduce its impact.
Find out how top security teams manage the crucial first hours with:
- Quick threat identification and risk assessment
- Simple steps for immediate response
- Effective collaboration with your SOC team
- Best practices for gathering evidence and investigating the breach
- Proven strategies for system recovery and future prevention
Step 2: Stop the Breach from Spreading
Next, you need to focus on preventing the escalation. For that, ensure that you revoke any compromised account access information immediately to prevent the attacker from gaining further access to sensitive systems or customer data.
For that,
- Isolate affected systems: Prevent the attacker from accessing more data or spreading to other parts of the network.
- Block malicious IPs: Stop any harmful IP addresses, disable compromised accounts, or cut off unauthorized access points.
Stopping the attacker from spreading ensures you can manage the cyber incident effectively.
Step 3: Identify if the Incident is Recent or Old
How you respond to a security incident depends on two things:
- The total duration the attacker has been inside your network or IT infrastructure.
- The documentation available for your network. This refers to the extent to which your network is documented and how easily your team can access detailed records about your infrastructure, systems, and configurations.
There are two main types of incident detection that security teams typically deal with:
- Incursion detection
- Persistence detection
| Factor | Incursion Detection | Persistence Detection |
|---|---|---|
| Description | Identifying recent attacks within the first 48 hours. | Attacker has been inside the network for months or years, with a persistent foothold. |
| Investigation Duration | 1–3 weeks | 2–4 months |
| Challenges | Easier to resolve and trace the root cause. | Harder to trace the root cause; investigation takes longer due to extended attacker presence. |
In persistence detection, the investigation usually takes longer because it’s harder to trace when and how the attack started. It is often drawn out because the information needed is slow to collect, and it’s hard to pinpoint the original infiltration point.
If your security system is capable of tracking attacker behavior, it can help in understanding the attacker’s tactics and movement faster and more efficiently.
- Suggested Reading: Advanced Network Traffic Analysis: Machine Learning and Its Impact on NTA
Once you determine if the breach is recent or continuing, you can apply a more focused data breach response process to reduce further damage and prevent future attacks.
Step 4: Respond to the Attacks
The main focus of incident response should be to stop the attacker from gaining a permanent foothold. Attackers often use custom malware, command-and-control setups, and exploits to get in.
Common attack techniques to watch for:
- Web server exploitation
- Email phishing campaigns
- Planting web shells
- SQL injections
Response Roles and Actions
Assign the roles and responsibilities to team members for a systematic incident response without any confusion.
The response team will continue carrying out their roles as outlined for the first 72 hours.
Check the below table for a better understanding:
| Timeframe | Role | Actions |
|---|---|---|
| 0-24 Hours | Network Admins | Pull network diagrams and identify involved IPs. |
| System Admins | Quarantine affected systems. | |
| Tech Admins | Collect copies of malware. | |
| Security Team | Identify tools that detect the attack, remove malware, set fraud alerts, and block malicious communication. | |
| Incident Response Lead | Initiate incident tracking and escalate the situation. | |
| Security Management | Report to executives and inform departments. | |
| 24-48 Hours | Network Admins | Continue classifying the network. |
| System Admins | Continue quarantining systems. | |
| Tech Admins | Analyze suspicious behavior. | |
| Security Team | Perform lookups for compromised IPs, accounts, and malware. Update security tools. | |
| Incident Response Lead | Begin documenting details, keep leadership informed. | |
| Security Management | Investigate the reason for the attack and support the IR team. | |
| 48-72 Hours | Network Admins | Maintain standby status. |
| System Admins | Continue quarantining systems. | |
| Tech Admins | Continue analyzing behaviors. | |
| Security Team | Finalize incident details and implement remediation measures. | |
| Incident Response Lead | Provide status updates, and formalize lessons learned | |
| Security Management | Prepare for post-incident training. |
For persistence detection incidents, internal teams may not have the required expertise to handle long term threats, particularly if the attacker has maintained access for months or years. In these cases, seeking external Incident Response teams is highly recommended.
The response activities include resetting user accounts, removing malware, remediating systems, blocking malicious IPs, and using custom signatures for active defense tools. In larger organizations, this could involve many user accounts, systems, and types of malwares.
These experts have the tools and knowledge to track and remove the threat, especially when it’s hard to find how the attacker got in. They also conduct thorough investigations to make sure no backdoors remain.
Even after isolating the breach and determining its scope, several challenges and delays could affect the overall effectiveness of your response.
Key challenges that can cause delays in incident response:
- Delays in Log Access: If logs aren’t retained or easily accessible, it can slow down the investigation.
- External Vendor Delays: Service providers (MSPs) may have strict rules about when they can make changes (like updating firewalls), causing delays in stopping attackers sooner.
- Poor Network Documentation: If there is no proper documentation of the system or network functionality and configuration, it’s difficult for the team to identify, contain, and eliminate the attackers, especially if the threat has been there for a long time.
Step 5: Eradication Planning for Persistent Attacks
In this step, you need to focus on:
- Documenting Affected Systems: Identify and record all compromised systems.
- Identifying Persistence Mechanisms: Locate malware or tools used for ongoing access (e.g., web shells, RATs).
- Assessing Network Vulnerability: Understand the intensity of the attack and which systems and accounts are affected.
Work on coordinated eradication:
- Reset User Accounts: Reset passwords and disable compromised accounts.
- Remove Malware: Thoroughly search for and eliminate malware.
- Block Malicious IPs: Block any attacker IPs or domains at the network perimeter.
- Deploy Active Defense: Implement custom signatures for antivirus and endpoint protection.
Coordinate across systems and user accounts to ensure thorough and efficient remediation. And keep the leadership and stakeholders updated at each step.
Post-Incident Review and Continuous Improvement
1. Root Cause Analysis
Use lessons learned to update your security protocols and strategies, such as fixing identified vulnerabilities, improving access controls, and providing detailed employee training on phishing and other social engineering tactics.
2. Update Response Plans and Improve Detection Capabilities
You should also focus on identifying the business requirements after data breach, such as increasing staff resources or investing in new tools for more efficient detection and prevention of future attacks.
3. Strengthen Business Continuity and Disaster Recovery Plans
Ensure that your business continuity plan after a data breach is well-established. This will help restore critical systems quickly and continue operations without any disruption.
4. Rebuild Trust with Stakeholders
A large part of rebuilding your consumer confidence after data breach involves communicating transparently with customers, partners, and internal teams about what happened and how you’re preventing future incidents.
5. Check Third-Party Security
Learn how Fidelis Elevate® helps you stay ahead with:
- Deeper visibility into your entire environment
- Real-time network traffic analysis
- Enhanced detection with rich metadata from NTA & EDR
- Cutting-edge endpoint protection
- Managed Detection and Response (MDR) for fast action
As you implement a robust security strategy post-breach, adopting an advanced security solution like Fidelis Elevate®, an XDR, can provide the comprehensive protection your organization needs to stay resilient against future threats.
Protect Your Data with Fidelis XDR: Stay One Step Ahead of Cyber Threats
Prevention is always better than cure. So, protect your data and IT infrastructure way ahead of threat actors with Fidelis.
A holistic approach with Extended Detection and Response (XDR) is essential to proactively protect your data and ensure business continuity.
Fidelis Elevate® is an industry-leading XDR platform that integrates Endpoint Security, Network Security, Deception, DLP, and Active Directory Protection in a single solution. With advanced capabilities, it helps you detect, assess, and mitigate threats faster and more effectively.
Why Fidelis Elevate®?
- End-to-End Visibility: Gain deep insight across network, endpoint, and cloud environments. Automatically map your cyber terrain and evaluate asset risks.
- Predictive Threat Detection: Use AI-powered analysis and MITRE ATT&CK mappings to anticipate adversary movements and respond faster.
- Active Deception Technology: Lure attackers with real-time decoys and breadcrumbs, catching threats others miss.
- Comprehensive Defense: Integrates threat detection, forensics, and response into one platform, providing proactive protection across all areas.
Download our Datasheet to learn more about Fidelis Elevate® and see how it can transform your cyber and data security landscape with its rich and advanced features.
Final Thoughts
After a breach, reviewing the incident and making continuous improvements helps your organization learn and grow stronger. By understanding the cause, updating your security plans, and rebuilding customer trust, you’ll be better prepared for future attacks. Ongoing monitoring and securing vendor relationships will keep you ahead of threats.
Now is the time to assess your incident response plan and ensure your team is ready. Strengthen your defenses and invest in ongoing improvement to stay protected!
Frequently Ask Questions
What should we do first after discovering a data breach?
The first step is to understand the breach. Then check if it’s a real security issue and figure out what sensitive data may be at risk, and plan how to respond. Make sure to isolate affected systems and notify stakeholders within the first 72 hours to contain the damage.
How can we stop a breach from spreading?
To stop a breach from spreading, you should:
- Isolate the affected systems to prevent further access to data.
- Block malicious IPs and disable compromised accounts to limit the attacker’s movement.
This helps ensure that the attack is contained and doesn’t escalate.
How do we know if the breach is recent or has been going on for a while?
A recent breach, called incursion detection, is easier to handle because the attacker hasn’t been in your system for long. It usually takes 1-3 weeks to investigate. However, if the attacker has been inside your network for months or even years (persistence detection), it can take longer to figure out when and how they entered, and the investigation may take 2-4 months.
How should we respond to the attack after the initial containment?
After isolating the breach, focus on preventing the attacker from maintaining a foothold. Common tactics to watch for include:
- Exploiting web servers, phishing emails, and social engineering attacks.
- Planting malware like web shells or executing SQL injections.
The goal is to eliminate these threats, block further attacks, and prevent the attacker from re-entering.
What steps should we take to fully eradicate the attack and prevent future incidents?
To fully eradicate the attack, you need to:
- Document affected systems and identify all compromised accounts.
- Remove malware and block malicious IPs to prevent re-entry.
- Reset user accounts and strengthen access controls.
- Ensure the team regularly reviews the systems, updates security tools, and learns from the breach to prevent future attacks.
