How severe is CVE-2025-64011?

CVE-2025-64011 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2025-64011 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-64011?

CVE-2025-64011 affects Nextcloud Nextcloud Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-64011?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2025-64011 have an EU (EUVD) identifier?

Yes. CVE-2025-64011 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-203106.

When was CVE-2025-64011 published?

CVE-2025-64011 was published on 2025-12-12 and last updated on 2026-06-17.

CVE-2025-64011

CVE-2025-64011 is a medium-severity vulnerability in Nextcloud Nextcloud Server with a CVSS 3.x base score of 4.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-639.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
EPSS exploit prediction: 0% (15th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-203106
Weakness: CWE-639
Affected product: Nextcloud Nextcloud Server
Published: 2025-12-12
Last modified: 2026-06-17

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.

Frequently asked questions

What is 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. This allows unauthorized disclosure of sensitive data, such as text files or images, without prior sharing permissions.
How severe is CVE-2025-64011?: CVE-2025-64011 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2025-64011 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-64011?: CVE-2025-64011 affects Nextcloud Nextcloud Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-64011?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-64011 have an EU (EUVD) identifier?: Yes. CVE-2025-64011 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-203106.
When was CVE-2025-64011 published?: CVE-2025-64011 was published on 2025-12-12 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:nextcloud:nextcloud_server:30.0.0:-:*:*:*:*:*:*

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