How severe is CVE-2025-66552?

CVE-2025-66552 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 none, integrity none, and availability low.

Is CVE-2025-66552 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-66552?

CVE-2025-66552 primarily affects Nextcloud Nextcloud Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-66552?

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

Does CVE-2025-66552 have an EU (EUVD) identifier?

Yes. CVE-2025-66552 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-201446.

When was CVE-2025-66552 published?

CVE-2025-66552 was published on 2025-12-05 and last updated on 2026-06-17.

CVE-2025-66552

CVE-2025-66552 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-778.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
EPSS exploit prediction: 0% (19th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-201446
Weakness: CWE-778
Affected product: Nextcloud Nextcloud Server
Published: 2025-12-05
Last modified: 2026-06-17

Description

Nextcloud Server is a self hosted personal cloud system. In Nextcloud Server and Enterprise Server prior to 30.0.9 and 31.0.1, incorrect path handling with groupfolders caused the admin_audit app to not properly log all actions on files and folders inside groupfolders. This vulnerability is fixed in Nextcloud Server and Enterprise Server prior to 30.0.9 and 31.0.1.

Frequently asked questions

What is CVE-2025-66552?: Nextcloud Server is a self hosted personal cloud system. In Nextcloud Server and Enterprise Server prior to 30.0.9 and 31.0.1, incorrect path handling with groupfolders caused the admin_audit app to not properly log all actions on files and folders inside groupfolders. This vulnerability is fixed in Nextcloud Server and Enterprise Server prior to 30.0.9 and 31.0.1.
How severe is CVE-2025-66552?: CVE-2025-66552 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 none, integrity none, and availability low.
Is CVE-2025-66552 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-66552?: CVE-2025-66552 primarily affects Nextcloud Nextcloud Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-66552?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-66552 have an EU (EUVD) identifier?: Yes. CVE-2025-66552 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-201446.
When was CVE-2025-66552 published?: CVE-2025-66552 was published on 2025-12-05 and last updated on 2026-06-17.

References

Affected products (2)

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

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