HackingEducationEducationCustomer Data InvolvedGovernment IDIdentity (basic)MediumContained

Millbrook School

bd_df56e7d39b154f15 · schema v1 · pii pii-v1

Severity

Medium

Discovered

Oct 20, 2020

Filed

Mar 22, 2021

To disclose

22 weeks

Affected · nationwide

4844 in this filing

Linked

4 filings

Confidence

66%

Full breach record for Millbrook School →

Millbrook School experienced an external system breach (hacking) on April 18, 2020, discovered on October 20, 2020. The incident compromised names and Social Security Numbers of 484 individuals, including 4 Maine residents. The school provided written notification on March 22, 2021, and offered 24 months of identity theft protection services.

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Maine clockDiscovered Oct 20, 2020 → Filed with AG Mar 22, 2021153d ✗ ME AG >90d22 weeks discovery → filing

⚠ unattributedNo provenance was recorded for this discovery date and it matches no other date on the record. It may be correct, but it is not independently grounded.

Incident timeline

undetected · 185 days

discovery → filing · 22 weeks / 153 days

Apr 18, 2020

Begins

Oct 20, 2020

Discovered

Mar 22, 2021

Filed

vs. sector median

+13 wks slower

This filing is one of 4 about the same incident.View merged incident

Part of BLACKBAUD, INC. supply-chain incident (2020) — a supply-chain cascade affecting multiple organizations.View cascade →

Linked disclosures

Why this link?

Regulatory filings (3) · sorted by filing gap

Indiana State AGbd_4debb556a0ac30012021-03-22Verified
New Hampshire State AGbd_36c204ef230469bb2021-03-23 · +1dVerified
Massachusetts State AGbd_4866dd6a89cc68052021-03-24 · +2dVerified

Name: Millbrook School
norm: millbrook school

Name: Millbrook School
norm: millbrook school
Industry: Educationllm

Discovered: Oct 20, 2020
Breach occurred: Apr 18, 2020
Undetected for: 185 daysoccurrence → discovery
Materiality determined: —
Notification sent: Mar 22, 2021
Affected individuals: 484state + nationwide
Data types: Government IDIdentity (basic)
Data elements: Social Security number
Attack vector: Unauthorized Access
MITRE ATT&CK: T1190 Exploit Public-Facing Application
Threat actor: External
Regulator citations: Filed data breach notice with Maine Attorney General
Initial access: exploit_public_facing

During the incident: Sent written notification to affected individuals
Offered 24 months of identity theft protection services
Source: Quoted from the filing itself, not independently verified.

Time to disclose: 22 weeks(153 days from discovery to filing)
Compliance flags: ME AG >90d · 153dME resident >60d · 153d
Discovery-date grounding: unattributedNo provenance was recorded for this discovery date and it matches no other date on the record. It may be correct, but it is not independently grounded.
Clock breakdown: Statute Window Elapsed Threshold Status
Maine
Discovered: Oct 20, 2020
→ Filed with AG: Mar 22, 2021
153d 90 days ME AG >90d
Maine
Discovered: Oct 20, 2020
→ Notified: Mar 22, 2021
153d 60 days (analyst band; statutory cap is 30 days) ME resident >60d

Statute	Window	Elapsed	Threshold	Status
Maine	Discovered: Oct 20, 2020 → Filed with AG: Mar 22, 2021	153d	90 days	ME AG >90d
Maine	Discovered: Oct 20, 2020 → Notified: Mar 22, 2021	153d	60 days (analyst band; statutory cap is 30 days)	ME resident >60d

Status: No extraction artifact recorded for this disclosure.

Filing propagation · 4 filings · 4 states

View merged incident ↗

Indiana State AGMar 22 · first

Maine State AGMar 22 · first · this page

New Hampshire State AG+1d

Massachusetts State AG+2d

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.maine.gov/agviewer/content/ag/985235c7-cb95-4be2-8792-a1252b4f8318/15893c72-b522-40c3-bf8c-e412b4e67286.shtml
DisclosureLens links to the originating regulator URL — full filing bodies are not redistributed from public surfaces (§4.5).
Filed at: Mar 22, 2021
Raw hash: 0ba49bcfea41f69af59cb2df625ebbc64f6a7382cb92916c1dc20f5a0659edc1

Linked disclosures

Regulatory filings (3) · sorted by filing gap

Reporting entityMillbrook School

Victim entityMillbrook School

Incidentdiscovered Oct 20, 2020

Stated responseSent written notification to affected individuals

ComplianceME AG >90d

Extraction provenanceno artifact recorded

Source provenancewww.maine.gov