Nextcloud Server 30.0.0 is vulnerable to an Insecure Direct Object Reference (IDOR) in the /core/preview endpoint.

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

1. Dec 12, 2025 · NIST NVD

   Detected

   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.

2. Oct 14, 2026 · NIST NVD

   Updated

   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.

Affected

• cpe nextcloud/nextcloud server30.0.0

Sources

• CVE.orgVulnerability recordCVE-2025-64011

  Official CVE identifier

  cve.org
• FIRST EPSSExploitation probabilityCVE-2025-64011

  30-day exploitation probability 0.3%

  first.org
• NIST NVDVulnerability recordCVE-2025-64011

  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 s

  nvd.nist.gov

References

• Exploit · drive.google.com
• Exploit · gist.github.com
• Product · nextcloud.com