{"id":"CVE-2021-22915","aliases":["EUVD-2021-10044"],"status":"published","description":"Nextcloud server before 19.0.11, 20.0.10, 21.0.2 is vulnerable to brute force attacks due to lack of inclusion of IPv6 subnets in rate-limiting considerations. This could potentially result in an attacker bypassing rate-limit controls such as the Nextcloud brute-force protection.","severity":{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-12","score":0.01739,"percentile":0.78055,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-307"],"published":"2021-06-11T15:49:38Z","modified":"2026-10-24T10:31:00Z","products":[{"vendor":"fedoraproject","product":"fedora"},{"vendor":"hackerone","product":"nextcloud server"},{"vendor":"nextcloud","product":"nextcloud_server"}],"references":[{"url":"https://hackerone.com/reports/1154003","tags":["x_refsource_MISC","x_transferred","Permissions Required","Third Party Advisory","report"]},{"url":"https://nextcloud.com/security/advisory/?id=NC-SA-2021-009","tags":["x_refsource_MISC","x_transferred","Broken Link","advisory"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L6BO6P6MP2MOWA6PZRXX32PLWPXN5O4S/","tags":["vendor-advisory","x_refsource_FEDORA","x_transferred","web"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AGXGR6HYGQ6MZXISMJEHCOXRGRFRUFMA/","tags":["vendor-advisory","x_refsource_FEDORA","x_transferred","web"]}],"sources":{"cve":[{"id":"CVE-2021-22915","description":"Nextcloud server before 19.0.11, 20.0.10, 21.0.2 is vulnerable to brute force attacks due to lack of inclusion of IPv6 subnets in rate-limiting considerations. This could potentially result in an attacker bypassing rate-limit controls such as the Nextcloud brute-force protection.","status":"published","published":"2021-06-11T15:49:38Z","modified":"2024-08-03T18:58:25.888Z","cwes":["CWE-307"],"updated_at":"2026-11-02T14:32:57.701381Z"}],"euvd":[{"id":"EUVD-2021-10044","description":"Nextcloud server before 19.0.11, 20.0.10, 21.0.2 is vulnerable to brute force attacks due to lack of inclusion of IPv6 subnets in rate-limiting considerations. This could potentially result in an attacker bypassing rate-limit controls such as the Nextcloud brute-force protection.","status":"published","published":"2021-06-11T15:49:38Z","modified":"2024-08-03T18:58:25Z","updated_at":"2026-11-03T03:25:01.154097Z"}],"nvd":[{"id":"CVE-2021-22915","description":"Nextcloud server before 19.0.11, 20.0.10, 21.0.2 is vulnerable to brute force attacks due to lack of inclusion of IPv6 subnets in rate-limiting considerations. This could potentially result in an attacker bypassing rate-limit controls such as the Nextcloud brute-force protection.","status":"published","published":"2021-06-11T16:15:11.913Z","modified":"2026-06-17T03:38:00.92Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:P/I:N/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-307"],"updated_at":"2026-11-02T14:06:54.439974Z"}],"osv":[{"id":"CVE-2021-22915","description":"Nextcloud server before 19.0.11, 20.0.10, 21.0.2 is vulnerable to brute force attacks due to lack of inclusion of IPv6 subnets in rate-limiting considerations. This could potentially result in an attacker bypassing rate-limit controls such as the Nextcloud brute-force protection.","status":"published","published":"2021-06-11T16:15:11.913Z","modified":"2026-10-24T10:31:00.254203559Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"updated_at":"2026-11-02T15:44:18.367807Z"}]}}