HackingFinancial ServicesFinanceStolen CredentialsCustomer Data InvolvedTargetedIdentity (basic)Government IDPIIMediumContained

Topstep LLC

bd_2541b774d1659019 · schema v1 · pii pii-v2

Severity

Medium

Discovered

Nov 26, 2025

Filed

Dec 22, 2025

To disclose

—

Affected

Not disclosed

Linked

5 filings

Confidence

66%

Full breach record for Topstep LLC →2 incidents on file

Topstep LLC notified affected individuals of a credential-stuffing attack discovered on November 26, 2025. Threat actors used stolen credentials from external sources to gain unauthorized access to user accounts. Potentially compromised data includes names, contact info, screen names, tax ID numbers, and Social Security Numbers. Topstep blocked attacker IPs, forced password resets, and offered 24 months of Experian IdentityWorks. Notifications were sent in December 2025.

J jump to incidentP pin to compareR raw source

Incident timeline

Nov 26, 2025

Begins

Nov 26, 2025

Discovered

Dec 22, 2025

Filed

This filing is one of 5 about the same incident.View merged incident

Linked disclosures

Why this link?

Regulatory filings (4) · sorted by filing gap

Texas State AGbd_03fab57c09efae722025-12-22Candidate
Massachusetts State AGbd_7451ebd5f9fa712a2025-12-22Verified
Massachusetts State AGbd_342fa38f154153c72025-12-30 · +8dCandidate
Nebraska State AGbd_716ada46a8c7b0a22025-12-30 · +8dVerified

Name: Topstep LLC
norm: topstep
Domain: topstep.com

Name: Topstep LLC
norm: topstep
Domain: topstep.com
Industry: Financial Servicesllm

Discovered: Nov 26, 2025
Breach occurred: Nov 26, 2025
Undetected for: 0 daysoccurrence → discovery
Materiality determined: —
Notification sent: Dec 26, 2025
Affected individuals: Not disclosed
Data types: Identity (basic)Government IDPII
Attack vector: Unauthorized Access
MITRE ATT&CK: T1078 Valid AccountsT1566.002 Spearphishing Link
Threat actor: ExternalFinancial
Initial access: valid_credentials

During the incident: Blocked the cyber threat actors’ IP address and account
Forced a password reset for all potentially affected accounts
Review its IT systems and security infrastructure
Update account login settings and processes to implement enhanced security measures
Offering complimentary access to Experian IdentityWorks SM for 24 months
Changes made: Update account login settings and processes to implement enhanced security measures
Source: Quoted from the filing itself, not independently verified.

Compliance flags: — (clock not assessable for this source)

Status: No extraction artifact recorded for this disclosure.

Filing propagation · 5 filings · 3 states

View merged incident ↗

Texas State AGDec 22 · first

Massachusetts State AGDec 22 · first

Nebraska State AGDec 22 · first · this page

Massachusetts State AG+8d

Nebraska State AG+8d

Pattern: first filing Dec 22 (TX), last Dec 30 (NE) — a 8-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://nebraska.gov/ago/data-breach/documents/c0d6d30f-1f31-4d39-92d4-4a9d7beda7f6.pdf
DisclosureLens links to the originating regulator URL — full filing bodies are not redistributed from public surfaces (§4.5).
Filed at: Dec 22, 2025
Raw hash: 02b90abbf8f602b934ef7a3687a082d021a5a49dea18c5e313c26ce7920a6037

Linked disclosures

Regulatory filings (4) · sorted by filing gap

Reporting entityTopstep LLC

Victim entityTopstep LLC

Incidentdiscovered Nov 26, 2025

Stated responseBlocked the cyber threat actors’ IP address and account

Complianceclock not assessable

Extraction provenanceno artifact recorded

Source provenancenebraska.gov