Password manager Dashlane has disclosed that "fewer than" 20 users on the personal subscription plan had their encrypted vaults downloaded following a brute-force attack launched by an unknown party.
On May 31, 2026, the company said an "external" threat actor launched a brute-force attack against certain Dashlane user accounts with the aim of breaking two-factor authentication (2FA) protections and allowing them to register new devices on existing user accounts.
Exactly how many users were targeted remains unknown, but Dashlane said the high volume of attempts on those accounts triggered temporary account suspensions and authentication issues due to its built-in security controls.
Although access to the accounts has since been restored, the company has now revealed that the attackers were successful in a handful of cases, enabling them to download a copy of the encrypted vaults belonging to less than 20 personal plan users.
"We have directly notified each of these users," it said. "If you're a Dashlane user and have not received a message from Dashlane specific to vault risk, there is no impact to your Dashlane account."
It's worth noting that the vault data cannot be accessed without the Master Password. Unless this password is trivial and highly predictable, it's unlikely that any attempts to crack open the vault will succeed. Dashlane also pointed out that its own internal systems were not impacted by the incident.
As a precautionary measure, users are advised to review the devices registered to their accounts and remove those they don't recognize, enable 2FA, and use a strong Master Password that's "long, unique, and difficult to guess."
Update
Dashlane has revealed that the threat actor targeted a device registration flow in the attack. This process is typically used to add a device, like a mobile phone or a computer, to a user's account. Specifically, the adversary has been found to target the API endpoints for device registration and use a brute-force attack to send a large volume of automated requests to those endpoints.
"When a user enables an additional device, Dashlane verifies the identity of the account holder," it explained. "This verification is completed by sending a one-time 6-digit token to the user's registered email address, or, for users who have enabled 2FA, by validating a 6-digit code generated by their authentication app."
"The user enters this code into the Dashlane application, at which point Dashlane registers the device and downloads a copy of the encrypted vault to the device."
Although Dashlane's security systems were automatically triggered to lock the targeted accounts as a safeguard, the password manager service said the threat actor managed to generate valid tokens for fewer than 20 personal plan customers that allowed them to register a new device on those accounts and download a copy of their encrypted vaults.
(The story was updated after publication on June 5, 2026, with additional details of the attack activity.)
