HackingOtherData ExfiltratedCustomer Data InvolvedIdentity (basic)LowContained

Cliff Viessman, Inc

bd_6a0be07d9d2a0689 · schema v1 · pii pii-v1

Severity

Low

Discovered

Aug 5, 2025

Filed

Sep 10, 2025

To disclose

5 weeks

Affected

3state residents only

Linked

6 filings

Confidence

66%

Full breach record for Cliff Viessman, Inc →

Cliff Viessman, Inc. notified Montana residents of a cybersecurity event discovered on August 5, 2025, where an unauthorized party accessed systems and copied files containing names and personal information. The company engaged forensic specialists, secured its network, and is offering 12 months of free credit monitoring. No misuse has been confirmed.

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Incident timeline

discovery → filing · 5 weeks / 36 days

Aug 5, 2025

Discovered

Sep 10, 2025

Filed

vs. sector median

3 wks faster

This filing is one of 6 about the same incident.View merged incident

Linked disclosures

Why this link?

Regulatory filings (5) · sorted by filing gap

Vermont State AGbd_2de4a46561dc03992025-09-10Verified
New Hampshire State AGbd_320845cb79cca05a2025-09-10Verified
Nebraska State AGbd_6766249f21ca103b2025-09-10Verified
Massachusetts State AGbd_6e2d97be442fbcbe2025-09-10Verified

Show 1 more filing ↓

Indiana State AGbd_9fa7938fd11a53da2025-09-10Verified

Name: Cliff Viessman, Inc
norm: cliff viessman

Name: Cliff Viessman, Inc
norm: cliff viessman
Industry: Otherllm

Discovered: Aug 5, 2025
Materiality determined: —
Notification sent: Sep 10, 2025
Affected individuals: 3state-resident count only
Data types: Identity (basic)
Attack vector: Unauthorized Access
MITRE ATT&CK: T1078 Valid AccountsT1041 Exfiltration Over C2 Channel
Threat actor: ExternalFinancial

During the incident: Took steps to lock down and secure our network
Engaged third-party cybersecurity specialists to assist with our response and to conduct a comprehensive forensic investigation
Reviewed the potentially impacted files to identify and catalog the types of information present within them
Implementing additional technical safeguards and enhanced security measures
Providing you with access to Single Bureau Credit Monitoring/Single Bureau Credit Report/Single Bureau Credit Score services at no charge
Providing you with proactive fraud assistance
Changes made: Implementing additional technical safeguards and enhanced security measures to mitigate against the risk of future issues
Source: Quoted from the filing itself, not independently verified.

Time to disclose: 5 weeks(36 days from discovery to filing)
Compliance flags: — (clock not assessable for this source)

Status: No extraction artifact recorded for this disclosure.

Filing propagation · 6 filings · 6 states

View merged incident ↗

Vermont State AGSep 10 · first

New Hampshire State AGSep 10 · first

Nebraska State AGSep 10 · first

Massachusetts State AGSep 10 · first

Indiana State AGSep 10 · first

Montana State AGSep 10 · 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/2025/09/Consumer-notification-letter-29.pdf
DisclosureLens links to the originating regulator URL — full filing bodies are not redistributed from public surfaces (§4.5).
Filed at: Sep 10, 2025
Raw hash: a899995490366d139f1c2f965bfb432174d06b28cc33bc08dcfeae3fc6b58fe8

Linked disclosures

Regulatory filings (5) · sorted by filing gap

Reporting entityCliff Viessman, Inc

Victim entityCliff Viessman, Inc

Incidentdiscovered Aug 5, 2025

Stated responseTook steps to lock down and secure our network

Complianceclock not assessable

Extraction provenanceno artifact recorded

Source provenancedojmt.gov