title: Username timing attack on recover password/MFA token in vantage6
description: vantage6 is an open source framework built to enable, manage and deploy privacy enhancing technologies like Federated Learning and Multi-Party Computation. Much like GHSA-45gq-q4xh-cp53, it is possible to find which usernames exist in vantage6 by calling the API routes `/recover/lost` and `/2fa/lost`. These routes send emails to users if they have lost their password or MFA token. This issue has been addressed in commit `aecfd6d0e` and is expected to ship in subsequent releases. Users are advised to upgrade as soon as a new release is available. There are no known workarounds for this vulnerability.
problem types: CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
affected:
{
vendor: vantage6
product: vantage6
versions:
version: <= 4.2.2, status: affected
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: NETWORK
availabilityImpact: NONE
baseScore: 5.3
baseSeverity: MEDIUM
confidentialityImpact: LOW
integrityImpact: NONE
privilegesRequired: NONE
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
version: 3.1
]