MasTec Data Breach History

This page tracks the MasTec data breach history and cybersecurity incidents affecting MasTec (United States). BreachHistory currently indexes 1 publicly disclosed or catalogued incident spanning 2025, with approximately 25 thousand records reported as exposed across all indexed events. These totals may include overlapping datasets or third-party estimates and should not be interpreted as unique affected users.

The MasTec breach timeline includes major data breaches, cyber attacks, data leaks, credential exposures, API abuse, and other security incidents. Each incident provides details on the estimated records exposed, attack method, affected data types, and supporting public sources. Currently, 0 incidents are company-confirmed.

Largest MasTec Data Breaches

The largest indexed incidents include the 2025 MasTec — third-party zero-day breach exposed 25,220 people (June 2026 notices). Record counts originating from threat actors or leak sites should be treated as estimates unless confirmed by MasTec or a regulator. Below is the list of large data breaches:

• 2025 2025 MasTec — third-party zero-day breach exposed 25,220 people (June 2026 notices) — about 25.2K records exposed · Catalogued incident

What Information Was Exposed?

Depending on the incident, exposed data may include passwords and login credentials, Social Security numbers and national IDs, names, physical addresses, and other personal information (PII). The exact data varies between incidents, so review each breach page before assuming your information was affected.

MasTec Data Breach 2026

At the time of this update, no MasTec data breach has been catalogued for 2026. New incidents are added as official disclosures, regulatory filings, or credible cybersecurity reports become available.

What To Do If You Were Affected

If you believe your account may have been involved in a MasTec data breach, change any reused passwords, enable multi-factor authentication (MFA), monitor your account for suspicious activity, and be cautious of phishing emails or fake breach notifications.

This MasTec breach history is maintained by BreachHistory using public disclosures, regulatory filings, security research, and clearly labelled third-party claims. For the complete breach timeline, records exposed, incident details, and AI Breach Risk Score, explore the sections on this page.