€3 Million Gone: How Deepfakes Fooled a Company's Own Bank

The voice on the call sounded exactly like a Capillary Technologies executive. It wasn't.

Capillary Technologies is a Bengaluru-based SaaS company with institutional backing and professional finance teams. Its overseas subsidiary had processes in place. None of that stopped a cloned voice and some forged paperwork from moving €3 million out the door. At the time of disclosure, the company had recovered €0.45 million, leaving roughly €2.55 million still missing.

This kind of fraud is no longer theoretical. In February 2024, engineering firm Arup lost $25 million when an employee joined a video call where every other participant was a deepfake. In the Capillary case, attackers didn't even need video.

How the Fraud Worked

The attack combined three techniques, none novel on their own, but together they worked. Voice cloning produced audio that sounded like Capillary's key managerial personnel. Modern tools can generate a convincing replica from as little as 20 to 30 seconds of audio, and earnings calls, conference presentations, YouTube videos, and LinkedIn posts all work as source material. Forged signatures added a paper trail that looked legitimate. When a voice says "transfer the funds" and a document arrives with a matching signature, the pressure to comply is real. Social engineering tied it together: the attackers knew enough about the company, its personnel, and its subsidiary structure to make the requests feel routine. That's not luck. That's research.

According to the World Economic Forum, deepfake fraud attempts increased 500% in 2024. The technology keeps getting cheaper, and the gap between what's real and what sounds real keeps narrowing.

Employees fall for this not because they're negligent, but because humans are wired to trust familiar voices. When a call sounds like a known executive and arrives with supporting documents, questioning it feels unnatural. Attackers research company structures in advance precisely because they know this.

The Verification Problem

Every fraud like this comes down to the same failure: someone couldn't verify they were actually talking to who they thought they were talking to. Phone numbers can be spoofed. Email accounts can be compromised. Voices can be cloned. Signatures can be forged.

What holds up is a shared secret: information only the real person would know, not publicly available, and rotated frequently enough to be useless if stolen.

Trust Onion gives finance and operations teams exactly that: three rotating codewords, calculated locally on authorized devices, that change every 60 seconds. Before approving a wire transfer or acting on an executive instruction, staff ask: "What are the words?" If the caller can't answer, the request stops there. The words are never sent to a server, work offline, and expire on a 60-second rotation. "Before I process this transfer, what are the words?" is a sentence that stops a cloned voice cold.

For teams that need to verify physical presence, a Proofie™ is a selfie signed using a passkey in the Trust Onion app. Verification checks the passkey signature against the full public key, the original photo's SHA-256 hash and byte length, and the signed record, including time and What3Words location. A valid Proofie establishes that whoever created the signed record possessed the private key at proof creation; compare the verified full signing key with the person's public key in your shared Trust Onion group.

A subsidiary receives what sounds like an urgent instruction from headquarters. The voice is convincing. The paperwork looks right. The window to think clearly is short.

Three words close that window on the attacker.

A controlled voice-cloning safety demonstration

Try our tool to see just how easy voice cloning is. This controlled safety demonstration exists only to show how easy voice cloning is and to make the risk tangible. It is not a real incident or proof of anyone's identity. Your submitted sample is handled transiently to generate the fixed demonstration audio. Trust Onion does not identify you or the person from the sample. Trust Onion does not store the submitted recording, clone, or generated audio.

Public by default, under your control. Proofie photos and signed records are stored securely on Amazon Web Services (AWS). A Proofie is public by default: anyone with its link or QR code can view the photo and signed record. You can add a password to make a Proofie private, or delete it at any time. Deleting a Proofie removes its photo and signed record from our AWS storage and takes its link offline, but cannot recall copies someone has already downloaded or saved.