What’s Vulnerable › Vulnerabilities

CVE-2021-32726: Webauthn tokens not removed after user has been deleted

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.8% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-07-12 · updated 2026-06-17
• Weakness: CWE-708

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.

Affected products

• Nextcloud Server: before 19.0.13; from 20.0.0 before 20.0.11; from 21.0.0 before 21.0.3 — fixed in 19.0.13, 20.0.11, 21.0.3

How to fix

Upgrade to a fixed version: Nextcloud Server 19.0.13, 20.0.11, 21.0.3. Check the vendor advisory for mitigations.

References

• https://github.com/nextcloud/security-advisories/security/advisories/GHSA-6qr9-c846-j8mg
• https://github.com/nextcloud/server/pull/27532
• https://hackerone.com/reports/1202590
• https://security.gentoo.org/glsa/202208-17
• https://github.com/nextcloud/security-advisories/security/advisories/GHSA-6qr9-c846-j8mg
• https://github.com/nextcloud/server/pull/27532
• https://hackerone.com/reports/1202590
• https://security.gentoo.org/glsa/202208-17

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