UnknownEducationEducationGovernment IDMedium

Chester County Library System, PA

bd_8944629f97ee5ee0 · schema v1 · pii pii-v1

Severity

Medium

Discovered

—

Filed

Nov 7, 2025

To disclose

—

Affected

5state residents only

Linked

3 records

Confidence

95%

Full breach record for Chester County Library System, PA →

Chester County Library System reported a data breach to the Massachusetts Office of Consumer Affairs and Business Regulation. The breach was reported on 2025-11-07. 5 Massachusetts residents were affected.

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Massachusetts clock✓ MA credit monitoring due

⚠ no discovery dateNo discovery date was extracted, so no notification clock can be evaluated.

Incident timeline — partial

? — ?

Breach window unknown

Nov 7, 2025

Filed

No interval is drawn: no breach start or discovery date is on record for this filing.

This filing is one of 3 records about the same incident.View merged incident

Linked disclosures

Why this link?

Ransomware claims (1)

Leak Sitelynxbd_e8349e010beea07a2025-10-21 · +17dCandidate

Regulatory filings (1) · sorted by filing gap

Maine State AGbd_19412a253040ab1e2025-10-28 · +10dVerified by operator

Name: Chester County Library System, PA
norm: chester county library system
Domain: ccls.org

Name: Chester County Library System, PA
norm: chester county library system
Domain: ccls.org
Industry: Educationregulator portal

Discovered: —
Materiality determined: —
Notification sent: —
Affected individuals: 5state-resident count only
Data types: Government ID
Data elements: Social Security numberDriver's licence number
Stated not affected: Medical informationFinancial account numberPayment card number
The filing states these were not involved. Categories absent from both lists were not addressed either way.
Attack vector: Unknown

Compliance flags: MA credit monitoring due
Discovery-date grounding: no discovery dateNo discovery date was extracted, so no notification clock can be evaluated.

Status: No extraction artifact recorded for this disclosure.

Filing propagation · 2 filings · 2 states

View merged incident ↗

Maine State AGOct 28 · first

Massachusetts State AG+10d · this page

Pattern: first filing Oct 28 (ME), last Nov 7 (MA) — a 10-day rolling notification. Rolling spreads often mean counsel is filing as thresholds trip per state. Why this link?

Evidence ladder

Leak-site claim

Attacker assertion only. Establishes: claim date, group, alleged victim.

Press / market report

Unlocks: incident narrative, operational impact. Still no compliance clock.

State AG / regulator filingThis record

Unlocks: discovery date, data types, affected count, compliance clock.

SEC 8-K / victim statement

Unlocks: materiality, stated response, full audit trail. Ceiling removed.

Source URL: https://www.mass.gov/doc/data-breach-report-2025/download
DisclosureLens links to the originating regulator URL — full filing bodies are not redistributed from public surfaces (§4.5).
Filed at: Nov 7, 2025
Raw hash: 1a6e4e0dfacac0af3c05ddfaa348c7e13b84a7002bd0acc5f665bbd10730e8fb

Linked disclosures

Ransomware claims (1)

Regulatory filings (1) · sorted by filing gap

Reporting entityChester County Library System, PA

Victim entityChester County Library System, PA

IncidentUnknown

ComplianceMA credit monitoring due

Extraction provenanceno artifact recorded

Source provenancewww.mass.gov