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.
CVSS Metrics
- Vector
- CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:H/A:N
- Attack Vector
- network
- Complexity
- low
- Privileges
- low
- User Action
- required
- Scope
- unchanged
- Confidentiality
- none
- Integrity
- high
- Availability
- none
- Weaknesses
- CWE-241
Metadata
- Primary Vendor
- NEXTCLOUD
- Published
- 12/5/2025
- Last Modified
- 12/10/2025
- Source
- NIST NVD
- Note: Verify all details with official vendor sources before applying patches.
Affected Products
nextcloud : calendarnextcloud : calendar
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