---
title: "Baydöner supplier-system data incident"
description: "Evidence-backed account of Baydöner supplier-system data incident, covering what happened, impact, timeline, attack vector, technical details, and primary sources."
incident_type: "Data incident"
status: "active"
last_modified: "2026-08-09"
canonical_url: "https://www.ally.security/incidents/baydoner-supplier-system-data-incident-2026"
markdown_url: "https://www.ally.security/incidents/baydoner-supplier-system-data-incident-2026.md"
stix_url: "https://www.ally.security/incidents/baydoner-supplier-system-data-incident-2026/stix.json"
---

# Baydöner supplier-system data incident

Baydöner said it found evidence that unauthorized people accessed supplier systems and that an independent technical investigation was continuing. Baydöner identified customer personal-data categories that may have been affected; HIBP separately characterized a verified incident corpus.

Last modified Aug 9, 2026 · 2 sources

## Summary

- **Environment:** Organization characterization; the notice did not name the supplier or a specific system.
- **Operational impact:** No outage or recovery duration quantified
- **Financial impact:** No public cost estimate

## What happened

[Baydöner](https://www.baydoner.com/) said it found evidence that unauthorized people accessed supplier systems and that an independent technical investigation was continuing. [1](#source-1)

## Impact

Baydöner identified customer personal-data categories that may have been affected; HIBP separately characterized a verified incident corpus. [1](#source-1) [2](#source-2)

Documented data types include:

- Names — Names identified by Baydöner as potentially affected and listed for the HIBP corpus. [1](#source-1) [2](#source-2)
- Purchase history — Order and delivery information identified by Baydöner as potentially affected; HIBP lists purchases. [1](#source-1) [2](#source-2)
- Contact information — Email addresses and phone numbers identified by Baydöner as potentially affected; HIBP lists the same classes. [1](#source-1) [2](#source-2)
- Geographic location information — Geographic locations listed only for the HIBP incident corpus; HIBP's description refers to cities of residence. [1](#source-1) [2](#source-2)
- Account credentials — Application passwords identified by Baydöner as potentially affected; HIBP lists passwords and separately characterizes them as plaintext in its description. [1](#source-1) [2](#source-2)
- Dates of birth — Dates of birth listed only for the HIBP incident corpus; Baydöner's public notice did not list this class. [1](#source-1) [2](#source-2)
- Government-issued identifiers — Turkish national identity numbers identified by Baydöner as potentially affected; HIBP lists government-issued IDs. [1](#source-1) [2](#source-2)
- Gender information — Gender information listed only for the HIBP incident corpus; Baydöner's public notice did not list this class. [1](#source-1) [2](#source-2)

A cited record reports 1,266,822 records (Unique email addresses represented in the HIBP incident corpus; a corpus-record count, not a Baydöner-confirmed number of affected customers or people; as of 2026-03-15). [1](#source-1) [2](#source-2)

Baydöner found evidence that unauthorized people accessed systems belonging to its suppliers. [1](#source-1)

Baydöner assessed that some customers' personal data may have been affected. [1](#source-1)

Baydöner said payment and financial data were not affected by the incident. [1](#source-1)

Baydöner advised customers to update the affected password and any reused passwords and to distrust unexpected email, SMS, or telephone requests. [1](#source-1)

## Timeline

### March 8, 2026 — Discovery

Date Baydöner said it detected the security event in supplier systems. [1](#source-1)

### March 8, 2026 — Documented event

HIBP BreachDate. Baydöner's notice says the supplier-system security event was detected on this date and does not establish an earlier public event-start date. [1](#source-1) [2](#source-2)

### August 9, 2026 — Briefing updated

This briefing was last reviewed and updated on August 9, 2026.

## Threat Group & Attack Vector

The cited public record does not establish a specific initial-access vector, malware family, exploited vulnerability, or ATT\&CK technique.

### 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

Baydöner said it would notify Turkey's Personal Data Protection Authority within the legal period. Baydöner said it sent individual notifications to all customers assessed as affected. Baydöner restricted access to its systems when it detected the event and launched an independent technical investigation. Baydöner said current findings indicated an externally sourced security vulnerability while an independent technical investigation into the cause remained in progress. No access path, attribution, scale, or recovery detail is inferred beyond the cited claims. [1](#source-1)

## Assets

[Download the case-scoped STIX 2.1 bundle](<https://www.ally.security/incidents/baydoner-supplier-system-data-incident-2026/stix.json>)

## Sources

Primary source records used to research this incident.

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

### Duyurular

advisory · Baydöner Restoranları A.Ş.

<https://www.baydoner.com/duyurular>

<a id="source-2"></a>

### Baydöner breach record

advisory · Have I Been Pwned · Mar 15, 2026

<https://haveibeenpwned.com/api/v3/breach/Baydoner>

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

Review the supporting structured claims.

1. **Discovered At · 100% confidence · current**  
   March 2026 Baydöner supplier-system incident: 2026-03-08
2. **Exposed Data Category · 90% confidence · current**  
   Baydöner customer-data exposure: Names
3. **Resulted In · 100% confidence · current**  
   March 2026 Baydöner supplier-system incident: Baydöner found evidence that unauthorized people accessed systems belonging to its suppliers.
4. **Exposed Data Category · 90% confidence · current**  
   Baydöner customer-data exposure: Purchase history
5. **Occurred At · 90% confidence · current**  
   March 2026 Baydöner supplier-system incident: 2026-03-08
6. **Exposed Data Category · 90% confidence · current**  
   Baydöner customer-data exposure: Contact information
7. **Resulted In · 100% confidence · current**  
   Baydöner public and customer notifications: Baydöner said it would notify Turkey's Personal Data Protection Authority within the legal period.
8. **Resulted In · 100% confidence · current**  
   Baydöner customer-data exposure: Baydöner assessed that some customers' personal data may have been affected.
9. **Resulted In · 100% confidence · current**  
   Baydöner public and customer notifications: Baydöner said it sent individual notifications to all customers assessed as affected.
10. **Resulted In · 100% confidence · current**  
   March 2026 Baydöner supplier-system incident: Baydöner restricted access to its systems when it detected the event and launched an independent technical investigation.
11. **Resulted In · 100% confidence · current**  
   Baydöner customer-data exposure: Baydöner said payment and financial data were not affected by the incident.
12. **Exposed Data Category · 80% confidence · current**  
   Baydöner customer-data exposure: Geographic location information
13. **Exposed Data Category · 90% confidence · current**  
   Baydöner customer-data exposure: Account credentials
14. **Exposed Data Category · 80% confidence · current**  
   Baydöner customer-data exposure: Dates of birth
15. **Resulted In · 100% confidence · current**  
   Baydöner public and customer notifications: Baydöner advised customers to update the affected password and any reused passwords and to distrust unexpected email, SMS, or telephone requests.
16. **Exposed Record Count · 100% confidence · current**  
   Baydöner customer-data exposure: 1,266,822 record
17. **Resulted In · 90% confidence · current**  
   March 2026 Baydöner supplier-system incident: Baydöner customer-data exposure
18. **Exposed Data Category · 90% confidence · current**  
   Baydöner customer-data exposure: Government-issued identifiers
19. **Affected Organization · 100% confidence · current**  
   March 2026 Baydöner supplier-system incident: Baydöner Restoranları A.Ş.
20. **Exposed Data Category · 80% confidence · current**  
   Baydöner customer-data exposure: Gender information
21. **Resulted In · 100% confidence · current**  
   March 2026 Baydöner supplier-system incident: Baydöner said current findings indicated an externally sourced security vulnerability while an independent technical investigation into the cause remained in progress.

</details>