What is CVE-2025-64011?

CVE-2025-64011 is a medium-severity vulnerability in Nextcloud Nextcloud_server, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 4.3/10. Published 2025-12-12.

How severe is CVE-2025-64011?

Medium severity. CVSS v3 base score is 4.3 out of 10.

Auth bypass in Nextcloud Nextcloud_server

CVE-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…

Vulnerability class: IDOR (Insecure Direct Object Reference)

EPSS: 0.002 (14.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N.

Affected products

Nextcloud Nextcloud_server — versions 30.0.0
N/a — versions n/a

Weakness classification (CWE)

CWE-639 — Authorization Bypass Through User-Controlled Key

References

cve@mitre.org (Exploit)
cve@mitre.org (Product)
cve@mitre.org (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2025-64011?: CVE-2025-64011 is a medium-severity vulnerability in Nextcloud Nextcloud_server, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 4.3/10. Published 2025-12-12.
How severe is CVE-2025-64011?: Medium severity. CVSS v3 base score is 4.3 out of 10.