Responding to a Data Breach: Steps to Take and Mistakes to Avoid

September 20, 2023

Despite best efforts to prevent them, data breaches are increasingly likely to occur as cyber threats grow more sophisticated. With average costs of a breach approaching $4 million, according to IBM, proper incident response is crucial for limiting damages. This article outlines key steps organizations should take when breached and common mistakes to avoid.

Assemble the Incident Response Team Immediately

At the first sign of a potential breach, convene the incident response team to coordinate efforts across security, legal, communications and other involved groups. Ensure team members understand their roles and responsibilities in the response process. Identify a main point of contact to streamline decision making. Document all actions taken for the investigation.

Contain the Breach to Prevent Further Data Loss

A top priority is containing the breach to prevent additional data loss. This can involve actions like:

  • Isolating or shutting down compromised systems
  • Revoking access for accounts used in the attack
  • Blocking suspicious IP addresses or disabling affected user credentials
  • Addressing vulnerabilities like unpatched software that allowed access

Take care to preserve evidence during containment. Avoid destroying logs, rebooting servers or other actions that could erase valuable forensic data for identifying the root cause.

Determine What Data Was Compromised and How

Conduct thorough investigation to determine the nature and scope of the breach. Retain digital forensics specialists as needed to analyze compromised systems and data logs. Key questions to answer include:

  • What specific data was accessed or acquired? This guides notification requirements.
  • How did the attack occur? Identify vulnerabilities like phishing, unpatched software or misconfigurations that led to access.
  • Did the attacker access other connected systems? Expand investigation to find the full extent of access.
  • Are there indicators of exfiltration or use of stolen data? Work with law enforcement to determine if stolen records are being misused.

Documenting details is critical for notifying affected individuals and organizations. It also aids investigation of how the attack happened to prevent repeat incidents.

Notify Impacted Individuals, Partners and Regulators

Once details are known, begin notifying all potentially impacted parties following breach notification laws and contractual obligations.

  • Individuals: Inform all those whose personal information was compromised. This includes current, former or prospective customers, employees and other parties.
  • Partners/Vendors: If a vendor or partner’s data was exposed in the breach, notify them even if not required by contract.
  • Law Enforcement: Contact appropriate agencies if cybercrime is involved. They may aid the investigation.
  • Regulators: Contact regulators in jurisdictions where affected individuals reside. Timely cooperation is key.

Provide specific, consistent details on the breach, data compromised, steps being taken, and resources to help minimize victim impact.

Eliminate Vulnerabilities That Led to the Breach

A critical step following any breach is addressing the weaknesses that allowed it to occur.

  • If unpatched software led to intrusion, implement patch management processes.
  • If phishing emails enabled malware installation, increase employee awareness training.
  • If misconfiguration allowed unauthorized access, review access controls for gaps.

Identifying and resolving root causes reduces the risk of similar future breaches.

Review and Improve Incident Response Processes

Conduct a post-mortem analysis of what worked and what didn’t in the response to improve plans before the next breach.

  • Gather feedback from all involved teams to identify gaps. Where were delays or confusion?
  • Update response playbooks with lessons learned and additional scenarios. Expand team training.
  • Implement new security controls and safeguards to address continuing risks identified.

Continuous improvement of response processes is key to minimizing business disruption.

Mistakes to Avoid When Responding to a Breach

While properly responding to breaches is challenging, there are common mistakes that can exacerbate fallout:

  • Delaying notification: Quick notifications that provide specific detail on the incident and how to mitigate risks demonstrates responsiveness. Avoid posting generic statements that downplay the breach.
  • Inconsistent information: Contradictory statements undermine credibility. Ensure all communications are coordinated and accurate.
  • Halting containment: Failures to stop additional data loss after discovery prolongs exposure. Continue containment efforts even during investigation.
  • Neglecting root causes: Not addressing vulnerabilities like unpatched systems or phishing exposes the organization to repeat incidents.
  • Lack of preparation: Breach response plans that sit on the shelf untested fail when needed most. Conduct response exercises to evaluate readiness.


While organizations should invest heavily in breach prevention, factors like human errors and increasingly sophisticated attacks make some breaches inevitable. Preparedness and proper response significantly mitigate potential damages. Quickly assembling a response team, containing the incident, investigating the root cause, notifying impacted parties and regulators, eliminating vulnerabilities, and improving plans for the next event are crucial steps. Avoiding common mistakes like delayed notifications, inconsistent communications and failing to address root causes optimizes the response. With cyber incidents on the rise, taking the time now to evaluate and refine data breach response plans pays dividends later.

Referenced Work

Marr, B. (2019, July 30). The 5 Biggest Data Breaches of 2019 So Far – And They Aren’t Over Yet. Forbes.

Responding to Data Breaches. (n.d.). Federal Trade Commission Consumer Information.

Data Breaches. (2021, November 10). Office for Civil Rights.

Verizon 2022 Data Breach Investigations Report. (2022). Verizon.

Incident response planning 101: How to prepare for data security incidents. (n.d.). Digital Guardian. Retrieved January 11, 2023, from