Is Open Finance safe? Real risks and how to protect yourself

"I am going to give an app access to my bank account? What if it leaks?" That suspicion is healthy. Money is sensitive, and every month brings news of a new scam. Before connecting anything to your bank, it makes sense to understand what is protecting you and what is not.

The short answer is that Open Finance Brasil was designed to be safer than the alternatives that existed before. The honest answer is that no system is risk-free, and the weakest link is usually a scam that tries to fool the person, not the technology.

In this guide you will see the layers of protection in Open Finance, the risks that really exist, how to recognize a fake screen, what to do if something goes wrong and a checklist for connecting your account with peace of mind.

The short answer: safe by design, not foolproof

Open Finance Brasil is regulated by Banco Central do Brasil, the country's central bank, and by the National Monetary Council (CMN). That means mandatory participation rules, common technical standards and supervision. It is not an informal agreement between companies.

Being "safe by design" means the system was built to limit damage even when something fails. Your data is not open to just anyone. Each access is authorized by you, with a defined scope and time limit, and travels through encrypted channels between authorized institutions.

But security is not an on-off switch. It is a sum of layers. Understanding each one helps you see where the risk really lies.

The layers of protection in Open Finance

Notice that no single layer solves everything. The strength is in the combination. Even if a receiving company had a problem, it would not have your password, it would only have the data you authorized, and only for a limited time.

Read-only vs payment initiation

There are two very different uses. Data sharing is read-only: the app sees your balance, statement or card bill, but cannot touch your money. Payment initiation allows an app to start a Pix payment (Pix is Brazil's instant payment system), but each payment must be approved by you in your bank's app.

If you only want to organize your finances, read-only access greatly reduces the risk. The worst case for a read-only app is exposure of information, not a withdrawal.

The real risks, honestly

Saying something is "100% safe" would be dishonest. These are the risks worth knowing:

1. Scams that imitate the consent screen

This is the most concrete risk. Scammers can create fake websites, messages or apps that copy the look of an Open Finance authorization and ask for your password, token or a code you received by text message. If you type it in, you have handed over the keys to your account, and that has nothing to do with real Open Finance.

2. Social engineering by phone or message

Someone pretends to be a bank or app employee, says they "need to validate your Open Finance" and asks you to approve something, share a code or make a "test" Pix. No bank does this. It is the same script as the most common Pix scams in Brazil, just with a different excuse.

3. Sharing more than you need

The consent is legitimate, but you approved data groups the app does not even use, or connected a service you no longer remember. It is not an intrusion, but it increases your exposure for no reason.

4. How the receiving company uses your data

The receiving institution must use the data only for the stated purpose, following the LGPD. Even so, choose companies that clearly explain what they do, where they store data and how you can request deletion.

5. Technical failures and incidents

Institutions, systems and suppliers can fail. The design of Open Finance reduces the impact (no password, limited scope, time limit), but it does not make incidents impossible.

How to recognize a fake screen

One rule covers almost everything: legitimate authorization ends inside your bank's official app, opened from your own phone, where you log in the usual way.

Warning signs:

• You are asked for your bank username and password on a website, form or inside an app that is not your bank's.
• You are asked for a verification code, token or password by phone, WhatsApp or email.
• The message arrives without you having started anything, with urgency ("your access will be blocked today").
• The link has a strange or shortened address, or typos.
• You are asked to make a Pix or transfer "to validate" the connection.

Open Finance vs other ways of giving access

To see why Open Finance is considered safer, compare it with the alternatives:

The spreadsheet is the most "closed" option, but it takes work and is often abandoned. Screen scraping is the riskiest: the app logs in as if it were you, which violates many banks' terms of use. Open Finance sits in the middle: convenience with control. If you are weighing manual tracking against an app, our guide on how to track expenses shows a routine that works either way.

A concrete scenario: what is at stake

Consider Rafael. He has R$ 3,500 in his checking account and R$ 12,000 in an emergency savings pocket at the same bank. He connects this account to a money management app.

If the connection is through Open Finance, read-only, the app can see the R$ 15,500 (3,500 + 12,000) and the statement. It cannot move a single cent. If the app had a security problem, the possible damage would be exposure of that information, which is bad, but does not empty the account.

Now imagine Rafael had fallen for a fake screen and typed in his bank password and the text message code. In that case, the scammer would have access to the bank app and could try to move the R$ 15,500, within the account's transaction limits. That is why the real danger is not in legitimate consent, but in a password handed over in the wrong place.

An extra protection that applies in both cases: Pix and transfer limits adjusted to your routine reduce the damage of any scam. In Brazil, night-time Pix (by default from 8 p.m. to 6 a.m.) is limited to R$ 1,000 for individuals unless you change it, and increases to limits take 24 to 48 hours to apply.

What to do if you suspect something

1. Revoke the suspicious consent in the Open Finance area of your bank's app.
2. Change your bank password if you typed it anywhere outside the official app.
3. Call your bank on the official number (on the back of your card or in the app), never on a number you received in a message.
4. Check statements and card bills from the last few days for strange transactions.
5. File a police report (boletim de ocorrência) if you lost money, and ask your bank to dispute the transaction through official channels. For Pix, banks use the MED, the Central Bank's Special Return Mechanism; a refund depends on there being money left in the scammer's account, so speed matters and it is not guaranteed.

If the problem involves the company that received your data, you can exercise your LGPD rights: request access to the information, correction or deletion.

Checklist before connecting your account

• Does the company clearly explain what it will use your data for?
• Were you taken to your bank's official app to authorize?
• Do the requested data groups make sense for the service?
• Is the authorization's time limit clear?
• Does the app request only read access, if all you want is to organize your finances?
• Do you know where to cancel later?

If the answer is "yes" to everything, the risk is low and well controlled. If anything feels off, stop.

How Otto handles security

Otto Finanças connects your accounts through Open Finance Brasil, via the aggregator Malvo, with read-only access. It does not ask for your bank password, does not make Pix payments and does not move money. You can cancel the connection in your bank's app or in Otto. And when you use the chat with Otto, the same rule applies as with any AI tool: never type passwords or codes, as we explain in using AI for personal finance safely.

Official sources and further reading

• Banco Central do Brasil: Open Finance regulation and security guidance (in Portuguese)
• Open Finance Brasil: official portal with explanations and participants
• General Data Protection Law, LGPD (Law 13,709/2018), in Portuguese