Description
Nextcloud Server 30.0.0 is vulnerable to an Insecure Direct Object Reference (IDOR) in the /core/preview endpoint. Any authenticated user can access previews of arbitrary files belonging to other users by manipulating the fileId parameter. This allows unauthorized disclosure of sensitive data, such as text files or images, without prior sharing permissions.
CVSS Metrics
- Vector
- CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
- Attack Vector
- network
- Complexity
- low
- Privileges
- low
- User Action
- none
- Scope
- unchanged
- Confidentiality
- low
- Integrity
- none
- Availability
- none
- Weaknesses
- CWE-639
Metadata
- Primary Vendor
- NEXTCLOUD
- Published
- 12/12/2025
- Last Modified
- 12/19/2025
- Source
- NIST NVD
- Note: Verify all details with official vendor sources before applying patches.
Affected Products
nextcloud : nextcloud_server
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