Pierce County Library System

Summary

The Pierce County Library System experienced a ransomware attack by the INC gang that exposed the personal information of more than 340,000 individuals. The breach forced the library to shut down all of its systems, disrupting access to physical branches, online catalogs, and digital services for patrons. Officials noted that the incident highlighted vulnerabilities in municipal networks and prompted a review of security protocols.

Motives

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TTPs

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Description

On December 15, 2025, a cyberattack was reported against the Pierce County Library System in Washington State. The attack resulted in the exposure of personal information belonging to more than 340,000 individuals. The breach was attributed to the INC ransomware gang. Following the incident, the library system was forced to shut down all of its IT systems. This shutdown halted all digital services offered by the library, including online catalog access and patron accounts. The public notice of the breach was issued on the same date.

The same source article also documented a variety of other cyber incidents occurring in late 2025 and early 2026. These included a cryptocurrency platform breach, a ransomware claim against the city of Meriden, Connecticut, and a malware attack on Passaic County, New Jersey. The article listed the Pierce County Library System breach alongside other notable cyber incidents. No further technical details about the attack vector or ransom demand were provided in the source. The library’s response was limited to the complete system shutdown as described in the report. The incident remains recorded as a significant data exposure affecting over three hundred thousand people.

Sources

Sources available to members: 1 source.