HackingProfessional ServicesProfessional ServicesStolen CredentialsData ExfiltratedTargetedIdentity (basic)LowResolved

EISNER ADVISORY GROUP LLC

bd_e35702ee8e886a3f · schema v1 · pii pii-v1

Severity

Low

Discovered

Sep 1, 2023

Filed

Apr 8, 2025

To disclose

20 months

Affected

249state residents only

Linked

12 filings

Confidence

65%

Full breach record for EISNER ADVISORY GROUP LLC →

Eisner Advisory Group LLC notified Montana residents of a data breach where unauthorized access occurred Sept 4-9, 2023. The incident involved the exfiltration of names and other personal info. Eisner discovered suspicious activity in Sept 2023, completed its investigation in Feb 2025, and sent notifications on April 8, 2025. Credit monitoring is offered.

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Incident timeline

Sep 4, 2023

Begins

Apr 8, 2025

Filed

vs. sector median

+65 wks slower

This filing is one of 12 about the same incident.View merged incident

Linked disclosures

Why this link?

Regulatory filings (10) · sorted by filing gap

Vermont State AGbd_0e87a3f3a7019a002025-04-08Verified
New Hampshire State AGbd_27e512fd0cdac5572025-04-08Verified
Washington State AGbd_61c9ad8db06a18a32025-04-08Candidate
Iowa State AGbd_9c143312e5d526b82025-04-08Verified

Show 6 more filings ↓

Oregon State AGbd_bd4df5a263203c7d2025-04-08Verified
Nebraska State AGbd_bf58b4074b8bdb072025-04-08Verified
Massachusetts State AGbd_c5bece9672884b592025-04-08Verified
Indiana State AGbd_ea112341cfa5a4d92025-04-08Verified
California State AGbd_ed6f19b468a372e92025-04-08Verified
Maine State AGbd_f8dee5063c7117622025-04-08Verified

Showing first 10 of 11 linked disclosures.

Name: EISNER ADVISORY GROUP LLC
norm: eisner advisory

Name: EISNER ADVISORY GROUP LLC
norm: eisner advisory
Industry: Professional Servicesllm

Discovered: Sep 1, 2023
Breach occurred: Sep 4, 2023 – Sep 9, 2023
Materiality determined: —
Notification sent: Apr 8, 2025
Affected individuals: 249state-resident count only
Data types: Identity (basic)
Attack vector: Unauthorized Access
MITRE ATT&CK: T1078 Valid AccountsT1119 Automated Collection
Threat actor: External
Regulator citations: Notified state and industry regulators
Initial access: valid_credentials

During the incident: Conducted a detailed review of the files determined to be at risk
Notified state and industry regulators
Notified law enforcement
Offering you complimentary access to 12/24 months of credit monitoring services
Source: Quoted from the filing itself, not independently verified.

Time to disclose: 20 months(585 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 · 11 states

View merged incident ↗

Vermont State AGApr 8 · first

New Hampshire State AGApr 8 · first

Washington State AGApr 8 · first

Iowa State AGApr 8 · first

Oregon State AGApr 8 · first

Nebraska State AGApr 8 · first

Massachusetts State AGApr 8 · first

Indiana State AGApr 8 · first

California State AGApr 8 · first

Maine State AGApr 8 · first

Montana State AGApr 8 · first · this page

Cascade drawn from the first 10 linked disclosures of 11 — 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://dojmt.gov/wp-content/uploads/2025/04/Consumer-notification-letter-8.pdf
DisclosureLens links to the originating regulator URL — full filing bodies are not redistributed from public surfaces (§4.5).
Filed at: Apr 8, 2025
Raw hash: 9d3a73a311ad835949dd8fbd1435abc021b6652021f907b97d03df7216551a78

Linked disclosures

Regulatory filings (10) · sorted by filing gap

Reporting entityEISNER ADVISORY GROUP LLC

Victim entityEISNER ADVISORY GROUP LLC

Incidentdiscovered Sep 1, 2023

Stated responseConducted a detailed review of the files determined to be at risk

Complianceclock not assessable

Extraction provenanceno artifact recorded

Source provenancedojmt.gov