MasTec Data Breach
Last Updated on June 9, 2026
At A Glance
- What's Going On?
- Attorneys need to hear from people affected by the MasTec data breach as they investigate whether a class action lawsuit can be filed.
- What You Can Do
- If you believe your information may have been compromised in the MasTec data breach, fill out the form on this page to learn more about the investigation and how you can help.
- Does This Cost Anything?
- It costs nothing to get in touch or to talk to someone about your rights.
- What Can I Get?
- If filed and successful, a class action lawsuit could provide consumers with money for any harm resulting from the MasTec breach.
MasTec Data Breach: Lawsuit Investigation
Attorneys working with ClassAction.org are looking into whether a class action lawsuit can be filed in light of the MasTec data breach.
As part of their investigation, they need to hear from individuals who had their information exposed in the incident, including those who received notice of the MasTec data breach or otherwise believe they are affected.
MasTec Security Incident: What Happened?
MasTec, an infrastructure construction company with offices nationwide, has reported a data breach affecting 25,220 people, involving unauthorized network access that resulted from a zero-day vulnerability in one of the company’s third-party vendors.
According to a letter sent to the New Hampshire Attorney General’s Office, MasTec was notified of suspicious activity at the site of one of its third-party solutions in October 2025, prompting a forensic investigation aided by cybersecurity specialists. Once the initial investigation identified the files affected by the MasTec data breach, a data review was conducted. In February 2026, the data-review vendor concluded that names, dates of birth, addresses, financial account details, Social Security numbers, and some account credentials were compromised.
MasTec mailed notification letters to impacted individuals on June 5 (see sample notice pictured below).
This cyberattack follows a 2023 incident that impacted approximately 22,000 current and former MasTec employees.
What You Can Do After the MasTec Data Breach
If your information was exposed in the MasTec data breach, attorneys want to hear from you. You may be able to start a class action lawsuit to recover compensation for loss of privacy, time spent dealing with the breach, out-of-pocket costs, and more.
A successful case could also force MasTec to ensure they take proper steps to protect the information they were entrusted with.
Affected by the MasTec data breach? Fill out the form on this page today.
Take Action
If you believe your information was exposed in the MasTec data breach, fill out the form on this page to get in touch with us.
An attorney or legal representative may then reach out to you to explain more about this investigation and ask you a few questions.
Remember, there is no cost to get in touch, and you are under no obligation to take action after speaking to someone.
Published: June 9, 2026
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The information submitted on this page will be forwarded to Bryson Harris Suciu & DeMay PLLC who has sponsored this investigation.
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