CVE-2025-66510: Nextcloud Server is a self hosted personal cloud system

Medium severity · published Dec 5, 2025

CVE-2025-66510

Nextcloud Server is a self hosted personal cloud system

4.9

CVSS

0.4%

EPSS

On KEV

Description

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.

CVSS vector

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

Attack vector

Network

Complexity

Low

Privileges

High

User interaction

None

Confidentiality

High

Integrity

None

Availability

None

Scope

Unchanged

Exploitation

Is it being used?

Exploit prediction (EPSS)0.4% · higher than 29% of CVEs

Exploited in the wildNo evidence yet

CISA KEVNot listed

Ransomware campaign useNot known

Affected products

Which versions

Nextcloud Server · Nextcloud

28.0.0 before 28.0.14.11; 29.0.0 before 29.0.16.8; 30.0.0 before 30.0.17.3; 31.0.0 before 31.0.10; 31.0.0 before 31.0.10; 32.0.0 before 32.0.1 · source: NVD

Affected product

Nextcloud Server

Nextcloud

All Nextcloud Server CVEs

References

NVD

https://nvd.nist.gov/vuln/detail/CVE-2025-66510

CVE.org

https://www.cve.org/CVERecord?id=CVE-2025-66510

Patch

https://github.com/nextcloud/security-advisories/security/advisories/GHSA-495w-cqv6-wr59

Patch

https://github.com/nextcloud/server/commit/e4866860cbf24a746eb8a125587262a4c8831c57

Issue Tracking

https://github.com/nextcloud/server/pull/55657