CVE-2026-45286: 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…

PriorityP423medium4.3CVSS 3.1

AVNACLPRLUINSUCLINAN

EPSS

0.28%

19.9th percentile

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.

Affected

4 ranges

Vendor	Product	Version range	Fixed in
nextcloud	calendar	>= 5.5.13 < 5.5.17	5.5.17
nextcloud	calendar	>= 6.2.0 < 6.2.3	6.2.3
nextcloud	security-advisories	—	—
nextcloud	security-advisories	—	—

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