{"cve":{"cve_id":"CVE-2021-20021","is_kev":true,"kev_date_added":"2021-11-03","kev_vendor_project":"SonicWall","kev_product":"SonicWall Email Security","kev_vulnerability_name":"SonicWall Email Security Improper Privilege Management Vulnerability","kev_short_description":"SonicWall Email Security contains an improper privilege management vulnerability that allows an attacker to create an administrative account by sending a crafted HTTP request to the remote host. This vulnerability has known usage in a SonicWall Email Security exploit chain along with CVE-2021-20022 and CVE-2021-20023 to achieve privilege escalation.","kev_required_action":"Apply updates per vendor instructions.","kev_due_date":"2021-11-17","kev_known_ransomware":true,"kev_notes":"https://nvd.nist.gov/vuln/detail/CVE-2021-20021","kev_cwes":["CWE-306"],"epss_score":0.83425,"epss_percentile":0.99643,"epss_as_of":"2026-06-23","description":"A vulnerability in the SonicWall Email Security version 10.0.9.x allows an attacker to create an administrative account by sending a crafted HTTP request to the remote host.","published_at":"2021-04-09T17:50:14Z","last_modified_at":null,"cvss_v3_score":9.8,"cvss_v3_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cvss_v3_severity":"CRITICAL","cvss_v4_score":null,"cvss_v4_vector":null,"cvss_v4_severity":null,"ssvc_decision":null,"ssvc_exploitation":"active","ssvc_automatable":true,"ssvc_technical_impact":"total","cwes":["CWE-269"],"nvd_references":["https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0007"],"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":"2026-06-24T00:09:31.350578Z","updated_at":"2026-06-28T23:14:51.606149Z"},"effective_severity":"CRITICAL","badges":["kev","ransomware","poc","epss"],"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":"U","value_label":"Unchanged"},{"metric":"C","name":"Confidentiality","value":"H","value_label":"High"},{"metric":"I","name":"Integrity","value":"H","value_label":"High"},{"metric":"A","name":"Availability","value":"H","value_label":"High"}]},"cvss_v4_decoded":{"version":null,"metrics":[]},"affected":[{"vendor_slug":"sonicwall","vendor_name":"SonicWall","product_slug":"email-security","product_name":"Email Security","version_start":"10.0.9 and earlier","version_start_inclusive":true,"version_end":"10.0.9 and earlier","version_end_inclusive":true,"cpe23_uri":"cve5:sonicwall:email-security:10.0.9 and earlier:10.0.9 and earlier"}],"exploit_refs":[{"source":"nuclei","kind":"nuclei","url":"https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2021/CVE-2021-20021.yaml","title":"SonicWall Email Security <= 10.0.9.x - Unauthenticated Admin Account Creation","author":"pussycat0x","disclosed_at":null}],"news":[],"references":[{"url":"https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0007","source_type":"VENDOR_ADVISORY","tags":["advisory"]}],"timeline":[{"type":"published","at":"2021-04-09T17:50:14Z","label":"CVE published","source":null},{"type":"cisa_reported","at":"2021-11-03T00:00:00Z","label":"Added to CISA KEV catalog","source":"kev"},{"type":"poc_available","at":"2026-06-24T00:29:48.638073Z","label":"Public PoC available","source":"nuclei"},{"type":"ssvc_changed","at":"2026-06-24T00:31:36.955378Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-06-24T00:31:36.955378Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-06-24T00:31:36.955378Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"cvss_changed","at":"2026-06-24T00:31:36.955378Z","label":"CVSS score revised","source":"vulnrichment"},{"type":"cvss_changed","at":"2026-06-24T00:31:36.955378Z","label":"CVSS score revised","source":"vulnrichment"},{"type":"cvss_changed","at":"2026-06-24T00:31:36.955378Z","label":"CVSS score revised","source":"vulnrichment"}]}