CVE-2026-45286
Medium
Description
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.
SeverityMedium
CVSS4.3
Exploit probability—
Product
Nextcloud Calendar
PublishedJun 1, 2026
First seenJun 1, 2026
Weakness typeCWE-200Sensitive information exposure
How to fix
Update
- nextcloud calendar5.5.17, 6.2.3 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| nextcloud calendar | 5.5.13 ≤ v < 5.5.17, 6.2.0 ≤ v < 6.2.3 | 5.5.17, 6.2.3 |
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