Vulnerability record · CVE-2025-66510 · published 5 December 2025

CVE-2025-66510: Nextcloud server vulnerability

Nextcloud · Nextcloud Server

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.

4.9 CVSS 3.1 Medium EPSS 0.36% · top 73.0% CWE-359 · CWE-359

4.9CVSS 3.1 base score

0.36%EPSS exploitation probability, 30 days

NoNot in CISA KEV

1Affected product versions listed by NVD

3References

17 Jun 2026Last modified by NVD

Description

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

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

Nextcloud Server Nextcloud

References

Link	Tags
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-495w-cqv6-wr59	PatchVendor Advisory
https://github.com/nextcloud/server/commit/e4866860cbf24a746eb8a125587262a4c8831c57	Patch
https://github.com/nextcloud/server/pull/55657	Issue Tracking

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2025-66510), CISA KEV, FIRST EPSS (scores of 2026-09-28). This page is refreshed as NVD updates the record.