medium5.7
CVE-2025-66550
Nextcloud Calendar is a calendar app for Nextcloud.
Impact
Nextcloud Calendar is a calendar app for Nextcloud. Prior to 4.7.17 and 5.2.4, when a malicious user creates a calendar event with a crafted attachment that links to a download link of a file on the same Nextcloud server, the file would be downloaded without the user confirming the action. This vulnerability is fixed in 4.7.17 and 5.2.4.
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Nextcloud | Calendar | from 4.0.0 before 4.7.17 from 5.0.0 before 5.2.4 |