Duo County Telephone Cooperative Corporation, Inc.

On May 15, 2025, the Maine Attorney General's Office disclosed a data breach affecting Duo County Telephone Cooperative Corporation, Inc. (operating as Duo Broadband). The incident, detected on March 17, 2025, involved unauthorized access to a database containing sensitive personal information of 42,518 individuals. Compromised data included full names, home addresses, dates of birth, and Social Security Numbers (SSNs) high-risk details frequently exploited for identity theft and financial fraud. The breach exposed customers to long-term vulnerabilities, including potential fraudulent account openings, loan applications, or tax fraud, given the permanence of SSNs. In response, the company partnered with Kroll to provide 12 months of identity theft protection services to affected individuals. However, the incident underscores systemic risks in telecommunications infrastructure, where third-party vendors or insufficient access controls may enable large-scale data exfiltration. The breach’s scale and the nature of the exposed data suggest prolonged operational and reputational consequences for the cooperative, including regulatory scrutiny, customer churn, and potential litigation.

Source: https://www.maine.gov/agviewer/content/ag/985235c7-cb95-4be2-8792-a1252b4f8318/943d1111-7f57-42a2-8259-b0de8e4ba981.html

TPRM report: https://www.rankiteo.com/company/duobroadband

"id": "duo301082125",
"linkid": "duobroadband",
"type": "Breach",
"date": "2/2025",
"severity": "85",
"impact": "4",
"explanation": "Attack with significant impact with customers data leaks"

{'affected_entities': [{'customers_affected': '42,518',
                        'industry': 'Telecommunications',
                        'name': 'Duo County Telephone Cooperative Corporation, '
                                'Inc.',
                        'type': 'Telecommunications Cooperative'},
                       {'customers_affected': '42,518',
                        'industry': 'Telecommunications',
                        'name': 'Cumberland Cellular, LLC (Duo Broadband)',
                        'type': 'Telecommunications Provider'}],
 'customer_advisories': ['Identity theft protection services offered through '
                         'Kroll for 12 months'],
 'data_breach': {'data_exfiltration': 'Yes',
                 'number_of_records_exposed': '42,518',
                 'personally_identifiable_information': ['names',
                                                         'addresses',
                                                         'dates of birth',
                                                         'Social Security '
                                                         'Numbers'],
                 'sensitivity_of_data': 'High',
                 'type_of_data_compromised': ['Personally Identifiable '
                                              'Information (PII)']},
 'date_detected': '2025-03-17',
 'date_publicly_disclosed': '2025-05-15',
 'description': "On May 15, 2025, the Maine Attorney General's Office reported "
                'a data breach involving Duo County Telephone Cooperative '
                'Corporation, Inc. and Cumberland Cellular, LLC (doing '
                'business as Duo Broadband). The breach, discovered on March '
                '17, 2025, involved unauthorized access to sensitive personal '
                'information of approximately 42,518 individuals, including '
                'names, addresses, dates of birth, and Social Security '
                'Numbers. Identity theft protection services were offered '
                'through Kroll for 12 months.',
 'impact': {'data_compromised': ['names',
                                 'addresses',
                                 'dates of birth',
                                 'Social Security Numbers'],
            'identity_theft_risk': 'High (PII exposed)'},
 'references': [{'source': "Maine Attorney General's Office"}],
 'regulatory_compliance': {'regulatory_notifications': ['Maine Attorney '
                                                        "General's Office"]},
 'response': {'third_party_assistance': ['Kroll (identity theft protection '
                                         'services)']},
 'title': 'Data Breach at Duo County Telephone Cooperative Corporation, Inc. '
          'and Cumberland Cellular, LLC (Duo Broadband)',
 'type': 'Data Breach'}