MalwareProfessional ServicesProfessional ServicesRansomwarePlay GroupPlayRansom DemandedData PublishedData ExfiltratedIdentity (basic)Government IDHealth (basic)Financial accountMediumContained

Mainelli Mechanical Contractors

bd_586c2060c7bd62ab · schema v1 · pii pii-v1

Severity

Medium

Discovered

Oct 17, 2024

Filed

Feb 19, 2025

To disclose

18 weeks

Affected

4state residents only

Linked

3 filings

Confidence

66%

Full breach record for Mainelli Mechanical Contractors →

Mainelli Mechanical Contractors, Inc. notified Montana residents of a ransomware incident involving the 'Play Group' on October 17, 2024. The attack potentially exposed personal information including SSNs, driver's licenses, medical info, and financial account numbers. Mainelli engaged outside cybersecurity experts, contained the threat, and is offering one year of credit monitoring via Experian.

J jump to incidentP pin to compareR raw source

Incident timeline

discovery → filing · 18 weeks / 125 days

Oct 17, 2024

Begins

Oct 17, 2024

Discovered

Feb 19, 2025

Filed

vs. sector median

1 wks faster

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

Linked disclosures

Why this link?

Ransomware claims (1)

Leak Siteplaybd_b13d9e0909e9bb912024-10-18 · +124dVerified

Regulatory filings (1) · sorted by filing gap

Maryland State AGPlay Groupbd_6351e1a7751f5dbd2025-02-19Verified

Name: Mainelli Mechanical Contractors
norm: mainelli mechanical contractors
Domain: mainellimechanical.com

Name: Mainelli Mechanical Contractors
norm: mainelli mechanical contractors
Domain: mainellimechanical.com
Industry: Professional Servicesllm

Discovered: Oct 17, 2024
Breach occurred: Oct 17, 2024
Undetected for: 0 daysoccurrence → discovery
Materiality determined: —
Notification sent: Feb 19, 2025
Affected individuals: 4state-resident count only
Data types: Identity (basic)Government IDHealth (basic)Financial account
Data elements: Social Security numberDate of birthMedical information
Attack vector: Ransomware· Play Group
MITRE ATT&CK: T1486 Data Encrypted for ImpactT1041 Exfiltration Over C2 ChannelT1530 Data from Cloud Storage Object
Threat actor: Play GroupExternalFinancial

During the incident: Took steps to block any unauthorized access to its network
Launched an investigation with the support of leading outside cybersecurity experts
Conducted a thorough review of the potentially affected systems
Implemented additional security measures designed to prevent a recurrence
Successfully removed the Play Group from Mainelli’s network
Offering one year of complimentary credit monitoring and identity restoration services through Experian
Changes made: Implemented additional security measures designed to prevent a recurrence of such an attack
Source: Quoted from the filing itself, not independently verified.

Time to disclose: 18 weeks(125 days from discovery to filing)
Compliance flags: — (clock not assessable for this source)

Status: No extraction artifact recorded for this disclosure.

Filing propagation · 2 filings · 2 states

View merged incident ↗

Maryland State AGFeb 19 · first

Montana State AGFeb 19 · first · this page

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/2025/03/Consumer-notification-letter-180.pdf
DisclosureLens links to the originating regulator URL — full filing bodies are not redistributed from public surfaces (§4.5).
Filed at: Feb 19, 2025
Raw hash: 8c78d1cdeaa31e63a34dcead0b92ed5d91a741e59a5959518d5c1240fa8a5c49

Linked disclosures

Ransomware claims (1)

Regulatory filings (1) · sorted by filing gap

Reporting entityMainelli Mechanical Contractors

Victim entityMainelli Mechanical Contractors

Incidentdiscovered Oct 17, 2024

Stated responseTook steps to block any unauthorized access to its network

Complianceclock not assessable

Extraction provenanceno artifact recorded

Source provenancedojmt.gov