CVE-2025-66510 MEDIUM

CVE-2025-66510: Nextcloud Server Contacts Search allowed users to retrieve contact information of other users beyond their contact list

Vendor Nextcloud
Product security-advisories
Weakness CWE-359
Published December 5, 2025
Last update December 5, 2025
View on NVD All CVEs

CVSS base score

4.5/10
Attack vector Network
Attack complexity Low
Privileges required High
User interaction Required
Confidentiality High
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:N/A:N

What the vulnerability does

01Description

Nextcloud Server is a self hosted personal cloud system. In Nextcloud Server prior to 31.0.10 and 32.0.1 and Nextcloud Enterprise Server prior to 28.0.14.11, 29.0.16.8, 30.0.17.3, and 31.0.10, contacts search allowed to retrieve personal data of other users (emails, names, identifiers) without proper access control. This allows an authenticated user to retrieve information about accounts that are not related or added as contacts.

Key dates

02Disclosure timeline

December 5, 2025 CVE published
December 5, 2025 Record updated