How severe is CVE-2021-32657?

CVE-2021-32657 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-2021-32657 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-32657?

CVE-2021-32657 affects Nextcloud Nextcloud Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-32657?

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

When was CVE-2021-32657 published?

CVE-2021-32657 was published on 2021-06-01 and last updated on 2026-06-17.

CVE-2021-32657

CVE-2021-32657 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-400.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
CVSS v2: 4.0
EPSS exploit prediction: 2% (76th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-400
Affected product: Nextcloud Nextcloud Server
Published: 2021-06-01
Last modified: 2026-06-17

Description

Nextcloud Server is a Nextcloud package that handles data storage. In versions of Nextcloud Server prior to 10.0.11, 20.0.10, and 21.0.2, a malicious user may be able to break the user administration page. This would disallow administrators to administrate users on the Nextcloud instance. The vulnerability is fixed in versions 19.0.11, 20.0.10, and 21.0.2. As a workaround, administrators can use the OCC command line tool to administrate the Nextcloud users.

Frequently asked questions

What is CVE-2021-32657?: Nextcloud Server is a Nextcloud package that handles data storage. In versions of Nextcloud Server prior to 10.0.11, 20.0.10, and 21.0.2, a malicious user may be able to break the user administration page. This would disallow administrators to administrate users on the Nextcloud instance. The vulnerability is fixed in versions 19.0.11, 20.0.10, and 21.0.2. As a workaround, administrators can use the OCC command line tool to administrate the Nextcloud users.
How severe is CVE-2021-32657?: CVE-2021-32657 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-2021-32657 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-32657?: CVE-2021-32657 affects Nextcloud Nextcloud Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-32657?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-32657 published?: CVE-2021-32657 was published on 2021-06-01 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:*

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