CVE-2025-66550
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.
Scoring
- Severity
- MEDIUM
- CVSS base score
- 5.7
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:H/A:N
- EPSS probability
- 0.34%
- CWE
- CWE-241
- Published
- 2025-12-05
- Last modified
- 2026-03-13
Affected products
- nextcloud security-advisories
- nextcloud security-advisories
Weakness type
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