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Incident

Health Insurance Marketplace

Incident posture

Attack window
Oct 2018
Location
United States of America
Status
Historical
CIA posture
Available to members
Updated
2026-07-16 16:13

Linked entities

Victim
Health Insurance Marketplace
Threat actors
0 actors
Sources
1 source

Timeline

Occurred
Oct 2018
Discovered
Pending
Disclosed
Pending
Resolved
Pending

Summary

Healthcare.gov experienced a data breach through anomalous activity in a broker assistance tool, potentially exposing information of up to 75,000 individuals. The Centers for Medicare & Medicaid Services detected the incident, secured the system, initiated an investigation, and notified law enforcement, though specifics of the compromised data were not disclosed. The breach led to the temporary suspension of the Direct Enrollment pathway used by brokers, occurring shortly before the annual open enrollment period for health insurance coverage.

Motives

Detailed motive labels are available to members.

0 motives

TTPs

Detailed technique labels are available to members.

1 technique

Description

On October 13, 2018, the Centers for Medicare & Medicaid Services (CMS) detected anomalous system activity within a Healthcare.gov tool designed for insurance brokers assisting consumers with coverage enrollment. CMS formally declared a security breach three days later on October 16. The federally operated health insurance marketplace breach potentially exposed files for approximately 75,000 individuals, though CMS did not specify the types of compromised information. The agency stated it adhered to standard security and risk protocols during investigation and reporting. Immediate containment measures included securing affected systems and consumer data, launching a further internal investigation, and notifying federal law enforcement agencies. CMS emphasized its commitment to assisting potentially impacted individuals and reinforcing consumer data protections. The Direct Enrollment pathway for brokers remained temporarily disabled following the incident, though Healthcare.gov’s core functions continued operating normally.

This incident occurred against a backdrop of longstanding security concerns regarding federal and state healthcare exchange platforms, including a 2014 Healthcare.gov intrusion that did not result in data leakage. The breach’s timing coincided with heightened operational significance, as it preceded the November 1 opening of the 2019 coverage open enrollment period—a critical six-week window for uninsured individuals to obtain coverage unless qualifying for Special Enrollment later. CMS did not publicly attribute the breach to specific threat actors or disclose technical details of the attack vector. The agency maintained public assurances about system integrity while managing reputational and operational challenges linked to the Affordable Care Act’s politically contested marketplace platform.

Sources

Sources available to members: 1 source.

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