---
title: "Harman Fitness network data incident"
description: "Harman Fitness notified individuals in October 2026 about unauthorized network access dating to September 2025."
incident_type: "Cybersecurity incident"
status: "active"
last_modified: "2026-10-13"
canonical_url: "https://www.ally.security/incidents/harman-fitness-network-data-incident-2025"
markdown_url: "https://www.ally.security/incidents/harman-fitness-network-data-incident-2025.md"
stix_url: "https://www.ally.security/incidents/harman-fitness-network-data-incident-2025/stix.json"
---

# Harman Fitness network data incident

Harman’s investigation identified possible access to personal-information files nearly a year after the network incident.

Last modified Oct 13, 2026 · 1 source

## Summary

- **Environment:** Harman Fitness computer network
- **Operational impact:** No operational-outage duration established
- **Financial impact:** No incident cost established in the reviewed evidence

## What happened

Harman Fitness reported unauthorized network access on September 4, 2025. Its [October 5, 2026 notice](https://oag.ca.gov/system/files/DBM-6073_HARMAN_L01_SAS_V2.pdf) describes possible access to personal-information files. [1](#source-1)

## Impact

Depending on information supplied, the affected fields included names, identity-document numbers, Social Security numbers, health and financial information, and bank-account details. Harman said banking passwords and bank information entered directly into [ADP](https://www.adp.com/) were excluded. [1](#source-1)

## Timeline

### September 4, 2025 — Unauthorized network access

The notice identifies this as the incident date. [1](#source-1)

### September 1, 2026 — Potential data impact identified

The investigation found possible access to personal-data files. [1](#source-1)

### October 5, 2026 — Consumer notice dated

Harman’s notification letter is dated October 5. [1](#source-1)

### October 13, 2026 — Briefing updated

This briefing was last reviewed and updated on October 13, 2026.

## Threat Group & Attack Vector

The notice does not identify the initial access method or an affected-person count. [1](#source-1)

### Actors

- No threat actor group has been identified in the reviewed public evidence.

### TTPs

- No specific MITRE ATT\&CK technique is currently mapped for this case.

## Response

Harman secured systems, retained forensic specialists and offered credit monitoring. The public template does not specify the monitoring duration. [1](#source-1)

## Assets

[Download the case-scoped STIX 2.1 bundle](<https://www.ally.security/incidents/harman-fitness-network-data-incident-2025/stix.json>)

## Sources

Primary source records used to research this incident.

<a id="source-1"></a>

### Harman Fitness notice of data breach

official · Harman Fitness · Oct 5, 2026

<https://oag.ca.gov/system/files/DBM-6073_HARMAN_L01_SAS_V2.pdf>

<details>
<summary>Evidence ledger</summary>

Review the supporting structured claims.

1. **Resulted In · 100% confidence · current**  
   Harman Fitness network data breach: Harman secured its systems, engaged external forensic specialists and offered credit-monitoring services; the public template leaves the subscription duration blank.
2. **Resulted In · 100% confidence · current**  
   Consumer notice dated: Harman’s consumer notice describing the September 2025 incident is dated October 5.
3. **Resulted In · 100% confidence · current**  
   Harman Fitness network data breach: Depending on information supplied, the notice lists names, Social Security numbers, driver’s-license or state-ID numbers, passports, health information, financial information, and bank-account and routing numbers.
4. **Resulted In · 100% confidence · current**  
   Harman Fitness network data breach: Consumer notice dated
5. **Resulted In · 100% confidence · current**  
   Potential personal-data impact determined: Harman determined that files containing personal information may have been accessed.
6. **Began At · 100% confidence · current**  
   Harman Fitness network data breach: 2025-09-04
7. **Resulted In · 100% confidence · current**  
   Harman Fitness network data breach: Harman reported unauthorized network access and possible access to files containing personal information.
8. **Resulted In · 100% confidence · current**  
   Harman Fitness network data breach: Potential personal-data impact determined
9. **Occurred At · 100% confidence · current**  
   Potential personal-data impact determined: 2026-09-01
10. **Occurred At · 100% confidence · current**  
   Consumer notice dated: 2026-10-05
11. **Resulted In · 100% confidence · current**  
   Harman Fitness network data breach: Harman said bank passwords and banking information entered directly into ADP were not impacted.
12. **Affected Organization · 100% confidence · current**  
   Harman Fitness network data breach: Harman Fitness

</details>