How severe is CVE-2021-32726?

CVE-2021-32726 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-32726 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-2021-32726?

CVE-2021-32726 affects Nextcloud Nextcloud Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-32726?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-32726 published?

CVE-2021-32726 was published on 2021-07-12 and last updated on 2026-06-17.

CVE-2021-32726

CVE-2021-32726 is a high-severity vulnerability in Nextcloud Nextcloud Server with a CVSS 3.x base score of 7.1. 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-287.

Key facts

Severity: High (CVSS 3.x base score 7.1)
CVSS v2: 7.5
EPSS exploit prediction: 2% (76th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Nextcloud Nextcloud Server
Published: 2021-07-12
Last modified: 2026-06-17

Description

Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.13, 20.011, and 21.0.3, webauthn tokens were not deleted after a user has been deleted. If a victim reused an earlier used username, the previous user could gain access to their account. The issue was fixed in versions 19.0.13, 20.0.11, and 21.0.3. There are no known workarounds.

Frequently asked questions

What is CVE-2021-32726?: Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.13, 20.011, and 21.0.3, webauthn tokens were not deleted after a user has been deleted. If a victim reused an earlier used username, the previous user could gain access to their account. The issue was fixed in versions 19.0.13, 20.0.11, and 21.0.3. There are no known workarounds.
How severe is CVE-2021-32726?: CVE-2021-32726 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-32726 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-2021-32726?: CVE-2021-32726 affects Nextcloud Nextcloud Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-32726?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-32726 published?: CVE-2021-32726 was published on 2021-07-12 and last updated on 2026-06-17.

References

Affected products (1)

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

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Other CWE-287 (Improper Authentication) vulnerabilities

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