MalwareProfessional ServicesProfessional ServicesRansomwareData EncryptedCustomer Data InvolvedIdentity (basic)Government IDFinancial accountMediumContained

L.M. Henderson & Company, LLP

bd_a55c8dc5a098a63e · schema v1 · pii pii-v1

Severity

Medium

Discovered

May 1, 2021

Filed

Sep 13, 2021

To disclose

15 weeks

Affected

4state residents only

Linked

3 filings

Confidence

67%

Full breach record for L.M. Henderson & Company, LLP →2 incidents on file

L.M. Henderson & Company, LLP experienced a ransomware incident in May 2021, potentially exposing personal information (names, addresses, DOBs, SSNs, financial account info) of 4 New Hampshire residents. The company engaged forensic investigators, notified law enforcement, reset passwords, and offered 12 months of credit monitoring.

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Incident timeline

discovery → filing · 19 weeks / 135 days

May 1, 2021

Discovered

Sep 13, 2021

Filed

vs. sector median

4 wks faster

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

Linked disclosures

Why this link?

Regulatory filings (2) · sorted by filing gap

Montana State AGbd_985f39c6cd3cd1232021-09-09 · +4dCandidate
Indiana State AGbd_4cb5227a0e0261002021-09-07 · +6dVerified

Name: L.M. Henderson & Company, LLP
norm: l m henderson company
Domain: wilsonelser.com

Name: L.M. Henderson & Company, LLP
norm: lm henderson
Industry: Professional Servicesllm

Discovered: May 1, 2021
Materiality determined: —
Notification sent: Sep 7, 2021
Affected individuals: 4state-resident count only
Data types: Identity (basic)Government IDFinancial account
Attack vector: Ransomware
MITRE ATT&CK: T1486 Data Encrypted for Impact
Threat actor: External
Regulator citations: Notified Attorney General John Formella, Office of the Attorney General

During the incident: Informed law enforcement
Worked with cybersecurity counsel to investigate how the Incident occurred and what information was compromised
Engaged a national cybersecurity firm to assist in assessing the scope of the incident
Took steps to mitigate the potential impact to our clients
Changing of all passwords within its environment
Offered complimentary identity theft and credit monitoring services for twelve (12) months
Changes made: Changing of all passwords within its environment
Review our current system, policies, and procedures and make any necessary adjustments
Source: Quoted from the filing itself, not independently verified.

Time to disclose: 15 weeks(105 days from discovery to filing)
Compliance flags: — (clock not assessable for this source)

Status: No extraction artifact recorded for this disclosure.

Filing propagation · 3 filings · 3 states

View merged incident ↗

Indiana State AGSep 7 · first

Montana State AG+2d

New Hampshire State AG+6d · this page

Pattern: first filing Sep 7 (IN), last Sep 13 (NH) — a 6-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://mm.nh.gov/files/uploads/doj/remote-docs/lm-henderson-20210913.pdf
DisclosureLens links to the originating regulator URL — full filing bodies are not redistributed from public surfaces (§4.5).
Filed at: Sep 13, 2021
Raw hash: 4c12b7cdc88a6895142523303284a458111053e085ff766b67a30b5ad5b2cffb

Linked disclosures

Regulatory filings (2) · sorted by filing gap

Reporting entityL.M. Henderson & Company, LLP

Victim entityL.M. Henderson & Company, LLP

Incidentdiscovered May 1, 2021

Stated responseInformed law enforcement

Complianceclock not assessable

Extraction provenanceno artifact recorded

Source provenancemm.nh.gov