CVE-2025-66550
Nextcloud Calendar attachments of local files are offered to downloaded
- State
- Published
- Severity
- 5.7 Medium
- Published
- Dec 5, 2025
- Updated
- Dec 5, 2025
- Reserved
- Dec 4, 2025
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 5.7 Medium | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:H/A:N | GitHub_M |
Weaknesses
- CWE-241 Improper Handling of Unexpected Data Type
Affected Products
| Product | Versions |
|---|---|
security-advisoriesnextcloud |
|
References
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