HackingTechnologyHealthcareInformationStolen CredentialsCapture Stored DataData ExfiltratedTargetedPIIIdentity (basic)Government IDPHIHealth (basic)MediumContained

EpiSource

bd_a2b82676192bff45 · schema v1 · pii pii-v1

Severity

Medium

Discovered

Feb 6, 2025

Filed

Sep 15, 2025

To disclose

32 weeks

Affected · nationwide

51 in this filing

Linked

24 filings

Confidence

66%

Full breach record for EpiSource →4 incidents on file

Episource, LLC submitted a supplemental notice to the New Hampshire Attorney General regarding a data security event. Unauthorized access occurred between January 27 and February 6, 2025, involving PHI and PII of healthcare plan members. The incident affected at least 5 individuals in NH (Blue Shield of California, MCS Healthcare Holdings, United Healthcare). Episource engaged law enforcement, contained systems, and offered credit monitoring.

J jump to incidentP pin to compareR raw source

Incident timeline

undetected · 10 days

discovery → filing · 32 weeks / 221 days

Jan 27, 2025

Begins

Feb 6, 2025

Discovered

Sep 15, 2025

Filed

vs. sector median

+13 wks slower

This filing is one of 24 about the same incident.View merged incident

Linked disclosures

Why this link?

Regulatory filings (10) · sorted by filing gap

California State AGbd_1b92ab769d91dc2a2025-09-11 · +4dVerified by operator
California State AGbd_9fdbc50e284e387e2025-09-22 · +7dVerified by operator
California State AGbd_f7b2fef6a5a68d492025-10-01 · +16dVerified by operator
California State AGbd_9fbf33f1d80fd6cd2025-10-15 · +30dVerified by operator

Show 6 more filings ↓up to 149d gap

California State AGbd_26b46fb1375699872025-11-12 · +58dVerified by operator
Montana State AGbd_8bfabd788a54c7dd2025-11-12 · +58dVerified by operator
Oregon State AGbd_a777c7526ecf94bd2025-12-11 · +87dVerified by operator
California State AGbd_e03b6cfce712071e2026-02-09 · +147dVerified by operator
New Hampshire State AGbd_5f78056b95d71c8e2026-02-10 · +148dVerified by operator
Texas State AGbd_902d3567da6db0052026-02-11 · +149dVerified by operator

Showing first 10 of 23 linked disclosures.

Name: EpiSource
norm: episource

Name: EpiSource
norm: episource
Industry: TechnologyllmHealthcarellm

Discovered: Feb 6, 2025
Breach occurred: Jan 27, 2025 – Feb 6, 2025
Undetected for: 10 daysoccurrence → discovery
Materiality determined: —
Notification sent: Sep 11, 2025
Affected individuals: 5state + nationwide
Data types: PIIIdentity (basic)Government IDPHIHealth (basic)
Attack vector: Unauthorized Access
MITRE ATT&CK: T1078 Valid AccountsT1119 Automated Collection
Threat actor: ExternalFinancial
Regulator citations: Supplemental Notice of Data Security Event to the Office of the New Hampshire Attorney General
Initial access: valid_credentials

During the incident: Hired a special team to help us
Called law enforcement
Turned off our computer systems
Offering two (2) years of free credit monitoring and identity theft protection services
Changes made: Making our computer systems even stronger than before
Source: Quoted from the filing itself, not independently verified.

Time to disclose: 32 weeks(221 days from discovery to filing)
Compliance flags: — (clock not assessable for this source)

Status: No extraction artifact recorded for this disclosure.

Filing propagation · 11 filings · 5 states

View merged incident ↗

California State AGSep 11 · first

New Hampshire State AG+4d · this page

California State AG+11d

California State AG+20d

California State AG+34d

California State AG+62d

Montana State AG+62d

Oregon State AG+91d

California State AG+151d

New Hampshire State AG+152d

Texas State AG+153d

Pattern: first filing Sep 11 (CA), last Feb 11 (TX) — a 153-day rolling notification. Rolling spreads often mean counsel is filing as thresholds trip per state. Why this link?

Cascade drawn from the first 10 linked disclosures of 23 — the full spread may be wider.

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://mm.nh.gov/files/uploads/doj/remote-docs/episource-20250915.pdf
DisclosureLens links to the originating regulator URL — full filing bodies are not redistributed from public surfaces (§4.5).
Filed at: Sep 15, 2025
Raw hash: 3789cddba255fe460b93b7859201d0409a818fd7818d73e0d9f4c513c7e85606

Linked disclosures

Regulatory filings (10) · sorted by filing gap

Reporting entityEpiSource

Victim entityEpiSource

Incidentdiscovered Feb 6, 2025

Stated responseHired a special team to help us

Complianceclock not assessable

Extraction provenanceno artifact recorded

Source provenancemm.nh.gov