Mack Energy Discloses Data Breach Following Ransomware Attack

On July 9, 2025, Mack Energy Corporation, an independent oil and gas company based in Artesia, New Mexico, became the victim of a ransomware attack orchestrated by the group Cicada3301. The attackers claimed responsibility on their dark web portal, stating they had exfiltrated approximately 3.1 terabytes of the company’s data.

The group threatened to publish the stolen information within 19 to 20 days and released sample screenshots as proof of their claim.

The breach was officially disclosed to the Texas Attorney General’s office on Nov. 7, 2025, nothing the breach affected at least 413 individuals in Texas and the compromised data included personally identifiable information such as names and Social Security numbers.

According to the Texas Attorney General’s data breach reports, Mack Energy notified affected consumers via U.S. Mail.

The scale of the attack, the volume of data stolen and the exposure of Social Security numbers indicate a severe breach with the potential for significant identity theft risks. The ransomware group’s public threat to release the data further increases the urgency for affected individuals to take protective action.

Mack Energy Corporation's response

Following the discovery of the breach, Mack Energy Corporation began notifying impacted individuals by U.S. Mail, as required by law. While specific details about the company’s internal response have not been publicly disclosed, it is standard practice in ransomware incidents of this scale for companies to work with cybersecurity experts and law enforcement to investigate the breach and secure their systems.

Given the exposure of names and Social Security numbers, affected individuals should remain vigilant for signs of identity theft. It is advisable to:

• Review credit reports for any unauthorized activity
• Consider placing a fraud alert or credit freeze with major credit bureaus
• Monitor financial accounts closely
• Be cautious of phishing emails or calls that may use stolen information