CVE-2025-66510

Nextcloud Server Contacts Search allowed users to retrieve contact information of other users beyond their contact list

MEDIUM
4.9
CVSS Score
Published: December 5, 2025 at 04:18 PM UTC
Updated: October 18, 2026 at 02:10 PM UTC
2 products affected across 1 vendorNextcloud/serversecurity-advisories

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Severity
MEDIUM4.9
Exploit prediction
EPSS 0.4%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

28.0.0 ≤ v < 28.0.14.1129.0.0 ≤ v < 29.0.16.830.0.0 ≤ v < 30.0.17.331.0.0 ≤ v < 31.0.1032.0.0 ≤ v < 32.0.1

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (3)

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
HIGH
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-359

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