AccidentalFinancial ServicesFinanceMisdeliveryCustomer Data InvolvedPIIFinancial accountLowResolved

TrailWest Bank

bd_6b3c8d795cb089b0 · schema v1 · pii pii-v1

Severity

Low

Discovered

Nov 12, 2024

Filed

Nov 21, 2024

To disclose

9 days

Affected

8state residents only

Confidence

64%

Full breach record for TrailWest Bank →2 incidents on file

TrailWest Bank notified Montana residents of a misdirected email incident on Nov 21, 2024. On Nov 6, 2024, an ACH Authorization form containing customer PII and financial account data was accidentally emailed to an external individual instead of an internal employee. The bank investigated, determined the recipient likely did not view the data, and offered free credit reports.

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Incident timeline

undetected · 6 days

discovery → filing · 9 days

Nov 6, 2024

Begins

Nov 12, 2024

Discovered

Nov 21, 2024

Filed

vs. sector median

7 wks faster

Tracked as a single-filing incident — the only disclosure on record for this event so far.Confirmed8 affectedView incident

Name: TrailWest Bank
norm: trailwest bank

Name: TrailWest Bank
norm: trailwest bank
Industry: Financial Servicesllm

Discovered: Nov 12, 2024
Breach occurred: Nov 6, 2024
Undetected for: 6 daysoccurrence → discovery
Materiality determined: —
Notification sent: Nov 21, 2024
Affected individuals: 8state-resident count only
Data types: PIIFinancial account
Attack vector: Unknown
MITRE ATT&CK: T1535 Untrusted Internal Component
Threat actor: External

During the incident: Immediately launched an investigation
Confirmed the unauthorized individual did not view any information
Taking steps to implement additional safeguards
Review policies and procedures relating to data privacy and security
Offered annual free credit report through TransUnion
Changes made: Implementing additional safeguards
Reviewing policies and procedures relating to data privacy and security
Source: Quoted from the filing itself, not independently verified.

Time to disclose: 9 days(9 days from discovery to filing)
Compliance flags: — (clock not assessable for this source)

Status: No extraction artifact recorded for this disclosure.

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/2025/02/Consumer-Notification-11.pdf
DisclosureLens links to the originating regulator URL — full filing bodies are not redistributed from public surfaces (§4.5).
Filed at: Nov 21, 2024
Raw hash: c362cb57f93a459279e007da487b31ef1abf872565af6132439d28770a91101c

Reporting entityTrailWest Bank

Victim entityTrailWest Bank

Incidentdiscovered Nov 12, 2024

Stated responseImmediately launched an investigation

Complianceclock not assessable

Extraction provenanceno artifact recorded

Source provenancedojmt.gov