{"cve":{"cve_id":"CVE-2021-32656","is_kev":false,"kev_date_added":null,"kev_vendor_project":null,"kev_product":null,"kev_vulnerability_name":null,"kev_short_description":null,"kev_required_action":null,"kev_due_date":null,"kev_known_ransomware":null,"kev_notes":null,"kev_cwes":null,"epss_score":0.01841,"epss_percentile":0.76216,"epss_as_of":"2026-06-23","description":"Nextcloud Server is a Nextcloud package that handles data storage. A vulnerability in federated share exists in versions prior to 19.0.11, 20.0.10, and 21.0.2. An attacker can gain access to basic information about users of a server by accessing a public link that a legitimate server user added as a federated share. This happens because Nextcloud supports sharing registered users with other Nextcloud servers, which can be done automatically when selecting the \"Add server automatically once a federated share was created successfully\" setting. The vulnerability is patched in versions 19.0.11, 20.0.10, and 21.0.2 As a workaround, disable \"Add server automatically once a federated share was created successfully\" in the Nextcloud settings.","published_at":"2021-06-01T21:45:11Z","last_modified_at":null,"cvss_v3_score":8.6,"cvss_v3_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N","cvss_v3_severity":"HIGH","cvss_v4_score":null,"cvss_v4_vector":null,"cvss_v4_severity":null,"ssvc_decision":null,"ssvc_exploitation":null,"ssvc_automatable":null,"ssvc_technical_impact":null,"cwes":["CWE-284"],"nvd_references":["https://github.com/nextcloud/security-advisories/security/advisories/GHSA-j875-vr2q-h6x6","https://hackerone.com/reports/1167853","https://security.gentoo.org/glsa/202208-17"],"vuln_status":null,"trending_score":null,"is_trending":false,"has_trended":false,"trended_number_one":false,"trending_peak_score":null,"trending_peak_rank":null,"started_trending_at":null,"trended_number_one_at":null,"summary_generated":null,"summary_generated_at":null,"summary_model":null,"created_at":"2026-06-24T00:09:39.878444Z","updated_at":"2026-06-28T23:15:39.534678Z"},"effective_severity":"HIGH","badges":[],"impact_analysis":[],"cvss_v3_decoded":{"version":"3.1","metrics":[{"metric":"AV","name":"Attack Vector","value":"N","value_label":"Network"},{"metric":"AC","name":"Attack Complexity","value":"L","value_label":"Low"},{"metric":"PR","name":"Privileges Required","value":"N","value_label":"None"},{"metric":"UI","name":"User Interaction","value":"N","value_label":"None"},{"metric":"S","name":"Scope","value":"C","value_label":"Changed"},{"metric":"C","name":"Confidentiality","value":"H","value_label":"High"},{"metric":"I","name":"Integrity","value":"N","value_label":"None"},{"metric":"A","name":"Availability","value":"N","value_label":"None"}]},"cvss_v4_decoded":{"version":null,"metrics":[]},"affected":[{"vendor_slug":"nextcloud","vendor_name":"nextcloud","product_slug":"security-advisories","product_name":"security-advisories","version_start":"< 19.0.11","version_start_inclusive":true,"version_end":"< 19.0.11","version_end_inclusive":true,"cpe23_uri":"cve5:nextcloud:security-advisories:< 19.0.11:< 19.0.11"},{"vendor_slug":"nextcloud","vendor_name":"nextcloud","product_slug":"security-advisories","product_name":"security-advisories","version_start":">= 20.0.0, < 20.0.10","version_start_inclusive":true,"version_end":">= 20.0.0, < 20.0.10","version_end_inclusive":true,"cpe23_uri":"cve5:nextcloud:security-advisories:>= 20.0.0, < 20.0.10:>= 20.0.0, < 20.0.10"},{"vendor_slug":"nextcloud","vendor_name":"nextcloud","product_slug":"security-advisories","product_name":"security-advisories","version_start":">= 21.0.0, < 21.0.2","version_start_inclusive":true,"version_end":">= 21.0.0, < 21.0.2","version_end_inclusive":true,"cpe23_uri":"cve5:nextcloud:security-advisories:>= 21.0.0, < 21.0.2:>= 21.0.0, < 21.0.2"}],"exploit_refs":[],"news":[],"references":[{"url":"https://github.com/nextcloud/security-advisories/security/advisories/GHSA-j875-vr2q-h6x6","source_type":"VENDOR_ADVISORY","tags":["advisory"]},{"url":"https://hackerone.com/reports/1167853","source_type":"MISC","tags":[]},{"url":"https://security.gentoo.org/glsa/202208-17","source_type":"MISC","tags":[]}],"timeline":[{"type":"published","at":"2021-06-01T21:45:11Z","label":"CVE published","source":null},{"type":"cvss_changed","at":"2026-06-28T17:18:31.722192Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:18:31.722192Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:18:31.722192Z","label":"CVSS score revised","source":"cvelistv5"}]}