Medium severity · published Dec 12, 2025
CVE-2025-64011
Nextcloud Server 30.0.0 is vulnerable to an Insecure Direct Object Reference (IDOR) in the /core/preview endpoint
4.3
CVSS
0.3%
EPSS
No
On KEV
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 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 interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 20% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NS
Nextcloud Server · Nextcloud
30.0.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-64011
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-64011
Exploit
https://drive.google.com/file/d/1eD3PN-u1caZYgGH96XHmJ7h_OBXEAHW4/view?usp=sharing
Exploit
https://gist.github.com/tarekramm/586dfe2d113fedfee6d71182570fc090
Product
https://nextcloud.com
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