How the Equifax Data Breach Happened

Authored By: Ankita Prajapati

The Equifax data breach of 2017 was one of the largest and most damaging data breaches in history.


It affected 143 million consumers in the United States, exposing sensitive information such as social security numbers, birth dates, addresses, and even some driver’s license numbers. In this case study, we will explore how the breach happened, what the consequences were, and what lessons can be learned from it.

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Equifax is one of the three largest credit reporting agencies in the United States, along with Experian and TransUnion. These companies collect and store vast amounts of personal and financial data about individuals, which is used to generate credit reports that lenders rely on to make lending decisions.

How the Breach Happened

In March 2017, the Department of Homeland Security issued a warning about a vulnerability in a popular web application framework called Apache Struts. Equifax’s IT team was responsible for patching any systems that used this framework, but they failed to do so in a timely manner.

As a result, when hackers discovered the vulnerability in Equifax’s systems, they were able to exploit it and gain access to sensitive data.

Once the hackers gained access to Equifax’s systems, they were able to move around undetected for months. They stole large amounts of data, and even created a backdoor that would allow them to access the system again in the future.


The Equifax data breach had far-reaching consequences for both individuals and the company itself. The stolen data included sensitive information such as social security numbers and birth dates, which could be used for identity theft and fraud.

Equifax’s response to the breach was also criticized for being slow and inadequate, which further damaged the company’s reputation.

In the aftermath of the breach, Equifax faced numerous lawsuits and investigations from regulatory bodies such as the Federal Trade Commission.

The company also agreed to pay a $700 million settlement to compensate affected individuals and improve its data security practices.

Lessons Learned

The Equifax data breach serves as a cautionary tale for companies that collect and store sensitive information about individuals.

There are several key lessons that can be learned from this incident:

  1. Patch vulnerabilities promptly: Equifax’s failure to patch the Apache Struts vulnerability in a timely manner was a key factor in the breach. Companies should have procedures in place to identify and patch vulnerabilities as soon as they are discovered.

  2. Invest in cybersecurity: Cybersecurity threats are constantly evolving, and companies need to invest in robust cybersecurity measures to protect their systems and data. This includes regular security audits, employee training, and the use of advanced technologies such as intrusion detection and prevention systems.

  3. Be transparent and responsive: Equifax’s slow and inadequate response to the breach was widely criticized. Companies should have a plan in place for how to respond to data breaches, including notifying affected individuals and regulatory bodies in a timely manner.

  4. Take responsibility: Equifax’s initial response to the breach was seen as defensive and deflective. Companies should take responsibility for any data breaches that occur and be transparent about what steps they are taking to prevent future incidents.

Be part of the Cybersecurity community


The Equifax data breach was a wake-up call for companies that handle sensitive information about individuals.

It highlighted the importance of investing in robust cybersecurity measures, promptly patching vulnerabilities, and having a plan in place for how to respond to data breaches.

By learning from the mistakes of Equifax, companies can take steps to improve their data security practices and better protect the privacy and security of their customers.

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