Bank Mandiri · Breach

Claim: actor offers 2026 Bank Mandiri debit card customer database

Nov 05, 2026 · 1 min read

A threat actor on a dark web forum claims to hold a 2026 database of Bank Mandiri debit card customers, one of Indonesia's largest banks, and is offering the full set for sale. The sample includes names, contact details, and card and account data such as transaction limits and fees. Nothing has been independently verified; if genuine, the data enables bank-impersonation calls, SMS and WhatsApp scams.

By HIFY Radar newsroom Updated 11/05/2026 05:15 AM Get this every day →← Back to the feed 1 source

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In this article

What happened
Why it matters
What to do
For the technical team
Timeline
Sources

What happened

A threat actor posted on a dark web forum a sample of what they claim is a 2026 database of Bank Mandiri debit card customers, one of Indonesia's largest banks, and is offering the full set for sale. The sample includes names, mobile numbers, email addresses, and card and account details such as transaction limits and fee data.

Why it matters

Nothing has been independently verified and the bank has not confirmed the incident. If the data is genuine, contact details tied to bank account data are ideal for convincing bank-impersonation calls, SMS and WhatsApp scams, creating fraud risk for the bank's customers.

What to do

Monitor customer channels for scam attempts in the bank's name, strengthen authentication on sensitive transactions, and warn customers to treat unexpected 'bank' contact with suspicion.

For the technical team

Affected: Bank Mandiri, um dos maiores bancos da Indonésia; base alegada de 2026 com dados de clientes de cartão de débito · Bank Mandiri debit card customers (alleged 2026 database).
Exploitation: Unverified claim by a threat actor on a dark web forum, reported by DailyDarkWeb. No confirmed exploitation.
Fix: No fix applicable (data leak).
Vector: Alleged data leak; no technical vector described. Origin and method used to obtain the database are not cited in the sources.
More details: The posted sample reportedly includes customer names, mobile numbers, email addresses, debit card and account details, transaction limits and fee data. Record count not disclosed. No confirmation from the bank. DailyDarkWeb notes this is an unverified threat-actor claim, not confirmation of a breach.