What happened
Retool disclosed that on 27 August 2023 an attacker phished an employee by SMS and then called them using an AI-generated clone of a colleague's voice, obtaining a multifactor code. Because Google Authenticator's then-new cloud sync feature backed up one-time-password seeds to the employee's Google account, capturing the account gave the attacker every OTP token. Twenty-seven cloud customers, all in the cryptocurrency sector, had their accounts accessed.
How the deception worked
The employee received a text claiming to be from Retool IT about a payroll and healthcare enrolment issue, with a link to a page cloning the company's internal identity portal. After the employee submitted credentials and an MFA code, the attacker phoned them; the voice was a deepfake of a specific IT team member the employee recognised, and the caller was familiar with office layout, colleagues and internal processes. During the call the employee provided an additional MFA code, which let the attacker add their own device to the employee's Okta account. From there they reached the employee's Google account, where Authenticator's cloud sync had backed up OTP seeds, and used those to pivot into internal admin systems and alter customer accounts.
AI involvement · Confirmed AI-enabled
Retool stated the caller used a deepfaked voice imitating a specific member of its IT team, whom the target employee knew. This is one of the earliest well-documented uses of voice cloning in a corporate intrusion.
The control that would have caught it· our reading, not a claim from the sources
Voice is no longer an identity proof; hardware security keys plus a policy that MFA codes are never read aloud, and disabling authenticator cloud sync on enterprise accounts, close both halves of this chain.
Sources (4)
- Retool blames breach on Google Authenticator MFA cloud sync featureBleepingComputer·bleepingcomputer.comOpen ↗
- Retool Falls Victim to SMS-Based Phishing Attack Affecting 27 Cloud ClientsThe Hacker News·thehackernews.comOpen ↗
- Google Feature Blamed for Retool Breach That Led to Cryptocurrency Firm HacksSecurityWeek·securityweek.comOpen ↗
- When MFA isn't actually MFARetool·retool.comOpen ↗
This entry summarises public reporting. It is not a legal finding, and details can change as investigations conclude. Found an error? Send a correction.