Hashicorp Vault has an Observable Discrepancy on Existing and Non-Existing Users
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Affected versions
0 → fixed in 1.20.1
Details
A timing side channel in Vault and Vault Enterprise’s (“Vault”) userpass auth method allowed an attacker to distinguish between existing and non-existing users, and potentially enumerate valid usernames for Vault’s Userpass auth method. Fixed in Vault Community Edition 1.20.1 and Vault Enterprise 1.20.1, 1.19.7, 1.18.12, and 1.16.23.
The fix
No fix commit could be resolved for this advisory (it may reference an issue tracker or a non-GitHub patch). See the references below.