Overview
- Researchers from ETH Zurich and USI detailed 27 attack scenarios against Bitwarden, LastPass, Dashlane and 1Password that challenge widely marketed zero‑knowledge guarantees under a malicious‑server model.
- The team logged 12 distinct attacks against Bitwarden, seven against LastPass and six against Dashlane, with more limited findings for 1Password, which also benefits from a high‑entropy secret key in its design.
- The attacks cluster around four areas: account recovery and key escrow, item‑level encryption lacking integrity, unauthenticated public keys in sharing features and downgrades driven by backwards‑compatibility.
- Outcomes include full vault compromise demonstrated for Bitwarden and LastPass and shared‑vault compromise for Dashlane, and many scenarios trigger during routine actions like login or sync; no in‑the‑wild exploitation is reported.
- Dashlane says it eliminated legacy crypto that enabled a downgrade attack, Bitwarden and LastPass report active hardening and remediation, and 1Password characterizes its issues as known architectural limitations while citing SRP and other controls.