title: Default settings leak federated cloud ID to lookup server of all users
description: Nextcloud Server is a Nextcloud package that handles data storage. Nextcloud Server versions prior to 19.0.11, 20.0.10, or 21.0.2 send user IDs to the lookup server even if the user has no fields set to published. The vulnerability is patched in versions 19.0.11, 20.0.10, and 21.0.2; no workarounds outside the updates are known to exist.
problem types: CWE-201: Insertion of Sensitive Information Into Sent Data
affected:
{
product: security-advisories
vendor: nextcloud
versions:
status: affected, version: < 19.0.11
status: affected, version: >= 20.0.0, < 20.0.10
status: affected, version: >= 21.0.0, < 21.0.2
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: NETWORK
availabilityImpact: NONE
baseScore: 2.7
baseSeverity: LOW
confidentialityImpact: LOW
integrityImpact: NONE
privilegesRequired: HIGH
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N
version: 3.1
]