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Confidentiality isn't your only concern. You should also be worried about integrity and availability. From "On The Security of Password Manager Database Forma

Confidentiality isn't your only concern. You should also be worried about integrity and availability. From "On The Security of Password Manager Database Formats": Unfortunately, [KDBX4] introduces new vulnerabilities. Similarly to KDB, the main problem of this format is the lack of authentication of *hdr*. As such, is it susceptible to modifications... This modification is not detectable by the password manager... if a user alters, and then saves, a corrupted database, all passwords previously affected by the attack are lost forever. This attack highlights a remarkable design flaw. Even an accidental bit-flip in the *pskey* field, e.g., due to a transmission error, cannot be detected, and leads to complete corruption of the database. Such corruption is unlikely to be immediately detected by users, who may subsequently add new entries. Over time, the database will be composed of both correct and corrupted entries, making it difficult to reconstruct the damaged records from a backup. Which reminds me - I need to migrate back to Password Safe as soon as possible.

negus 11y ago
Confidentiality is my only concern in the case of malicious modification. Remember, that availability and integrity of your database can be broken without an attacker, just due to hardware problem, for example. So it is up to you to have a cold backup for such a critical asset.
- xenophonf 11y ago
  May I emphasize this sentence? Over time, the database will be composed of both correct and corrupted entries, making it difficult to reconstruct the damaged records from a backup. I don't know enough about cryptography to be able to say whether it's possible to break a particular cryptographic protocol by blindly altering the ciphertext, but I do know plenty about human nature and backups. It's _highly_ unlikely that normal people keep more than a handful of backups. My own personal backup retention limit is on the order of 30 days, and that's with careful planning. Silent, on-going data corruption happening to a password database seems like a very reasonable thing to concern oneself with, especially if one's expectation was that the password manager would throw some kind of data integrity error whenever said database was accessed.
salibhai 11y ago
How will you do that? It looks tricky to say the least: http://sourceforge.net/p/passwordsafe/discussion/134801/thread/3753e2c7/ http://sourceforge.net/p/passwordsafe/discussion/134801/thre... EDIT: It looks like you can clear out all the comments and other stuff in the db and export to Keepass v1 CSV and you should be able to import from that.
- xenophonf 11y ago
  Hey, thanks a ton for the clue!
debfx 11y ago
This isn't true anymore. Newer versions store a SHA-256 hash of the header inside the encrypted XML. At least KeePass >= 2.20 and KeePassX 2.0 >= alpha3 support this. I haven't checked other implementations.

negus 11y ago

Confidentiality is my only concern in the case of malicious modification. Remember, that availability and integrity of your database can be broken without an attacker, just due to hardware problem, for example. So it is up to you to have a cold backup for such a critical asset.

xenophonf 11y ago
May I emphasize this sentence? Over time, the database will be composed of both correct and corrupted entries, making it difficult to reconstruct the damaged records from a backup. I don't know enough about cryptography to be able to say whether it's possible to break a particular cryptographic protocol by blindly altering the ciphertext, but I do know plenty about human nature and backups. It's _highly_ unlikely that normal people keep more than a handful of backups. My own personal backup retention limit is on the order of 30 days, and that's with careful planning. Silent, on-going data corruption happening to a password database seems like a very reasonable thing to concern oneself with, especially if one's expectation was that the password manager would throw some kind of data integrity error whenever said database was accessed.

salibhai 11y ago

How will you do that? It looks tricky to say the least: http://sourceforge.net/p/passwordsafe/discussion/134801/thread/3753e2c7/ http://sourceforge.net/p/passwordsafe/discussion/134801/thre... EDIT: It looks like you can clear out all the comments and other stuff in the db and export to Keepass v1 CSV and you should be able to import from that.

xenophonf 11y ago
Hey, thanks a ton for the clue!

debfx 11y ago

This isn't true anymore. Newer versions store a SHA-256 hash of the header inside the encrypted XML. At least KeePass >= 2.20 and KeePassX 2.0 >= alpha3 support this. I haven't checked other implementations.