The LastPass 2022 Breach Explained: What Was Stolen, What It Means, and How to Migrate Off
In August / November 2022, attackers exfiltrated LastPass cloud backups including encrypted user vaults plus unencrypted metadata. Here is what is documented and what to do now if you still have a LastPass account.
Documented timeline
Per LastPass's published incident notices: in August 2022, attackers compromised a LastPass developer's machine and accessed source code. In November 2022, attackers used credentials from the August incident to access cloud backups in LastPass's third-party cloud storage. Those backups contained encrypted customer vaults plus unencrypted metadata — vault URLs, account email addresses, billing information. LastPass disclosed the data theft on December 22, 2022 (blog.lastpass.com/posts/notice-of-recent-security-incident).
What the encryption actually protects
LastPass vaults are encrypted with AES-256, with the key derived from the master password via PBKDF2. The strength of the protection depends on (a) the master password's entropy and (b) the PBKDF2 iteration count. LastPass's PBKDF2 default iteration count was 5,000 for old accounts before being increased to 100,100 in 2018. Accounts created before 2018 may still have low iteration counts unless the user manually upgraded — LastPass's incident notices document this. A weak master password with low iteration count is brute-forceable offline; a strong master password with 100,100+ iterations is not, with current hardware.
What to do if you have or had a LastPass account
Step 1: Export your LastPass vault from the web console (Settings → Advanced Options → Export). Step 2: Import into Bitwarden or 1Password (both have direct LastPass importers documented at bitwarden.com/help/import-from-lastpass and 1password.com/help). Step 3: Rotate passwords on any account with high disclosure cost — financial, email, primary social. Step 4: Enable 2FA on any account that supports it. Step 5: Delete the LastPass account from the web console. If your master password was strong (12+ random characters or 6+ word passphrase), the encrypted vault is computationally safe; rotation is precautionary. If your master password was weak, treat the high-value accounts as compromised.
Why the breach affected the password-manager category, not just LastPass
The LastPass breach prompted security researchers to look more carefully at the architectural choices across the category. Two specific learnings: (1) Encryption iteration counts are not all equal — the difference between 5,000 and 100,100 PBKDF2 iterations is large. Argon2id (the modern KDF used by Bitwarden and others) is materially stronger again. (2) Metadata exposure (URLs of accounts, email addresses) is a real privacy harm even when vault contents remain encrypted, because the metadata helps an attacker prioritise targets. Modern audited managers limit metadata in the data-at-rest layer.
Sources
LastPass official incident notices: blog.lastpass.com/posts/notice-of-recent-security-incident. Bitwarden LastPass importer: bitwarden.com/help/import-from-lastpass. 1Password help: 1password.com/help. Argon2id: password-hashing.net/argon2-specs.pdf. All URLs accessed 2026-04-30.