CVE-2026-45286
Nextcloud: Calendar app leaked user identifiers via attendee suggestion endpoint
CVSS Score
4.3
EPSS Score
0.0%
EPSS Percentile
0th
Nextcloud is an open source content collaboration platform. From versions 5.5.13 to before 5.5.17, and 6.2.0 to before 6.2.3, an authenticated user can enumerate users on the same Nextcloud instance by using the Calendar app's endpoint for suggesting attendees. The sharing restrictions, applied to other endpoints, were not effective here. This issue has been patched in versions 5.5.17 and 6.2.3.
| CWE | CWE-200 |
| Vendor | nextcloud |
| Product | security-advisories |
| Published | Jun 1, 2026 |
| Last Updated | Jun 1, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
None
Affected Versions
nextcloud / security-advisories
>= 5.5.13, < 5.5.17 >= 6.2.0, < 6.2.3