The article is nearly useless for users of the software who want to know how their data may have been affected. The researchers' website is more descriptive, especilly wrt specific findings. https://zkae.io/
Issue 5: Organisation Key Injection (Medium)
When users interact with organizations, a trust relationship is established through the exchange of cryptographic keys. A malicious server could add users to arbitrary organizations by encrypting an organization symmetric key under the user's public key and including it in sync responses. The client would silently accept the new organization membership. Alternatively, when a user creates an organization, the malicious server could substitute the newly created organization's keys with attacker-controlled keys during the post-creation sync.
Issue 7: Disable KDF Bruteforce Protection (Low)
Bitwarden uses Password-Based Key Derivation Functions (PBKDF2 or Argon2id) to derive the master key from the user's master password. The iteration count – currently defaulting to 600,000 for PBKDF2 – provides brute-force resistance. The researchers identified that KDF settings are stored on the server without authentication, allowing a malicious server to reduce the iteration count and receive a master key hash that is faster to brute-force.
Issue 9: Malleable Vault Format and Unencrypted Metadata (Low)
The researchers identified that while individual fields are encrypted, metadata about field positions and item structure is not integrity-protected, potentially allowing field reordering or item manipulation
Issue 10: Access Violation in Organisation Collections (Low)
Organization collections enable shared access to vault items among organization members. By design, the organization symmetric key is shared with all organization members, allowing them to access collection contents to which they have specifically been granted access