{"schema":"threatline.record/2","record":{"id":"CVE-2021-40539","aliases":[],"summary":"Zoho ManageEngine ADSelfService Plus Authentication Bypass Vulnerability","details":"Zoho ManageEngine ADSelfService Plus contains an authentication bypass vulnerability affecting the REST API URLs which allow for remote code execution.","categories":["Applications & CMS"],"product":"ManageEngine","vendor":"Zoho","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2021-40539","source_modified_at":"2025-10-21T23:25:35.374Z","fetched_at":"2026-10-23T18:42:43.628194Z","product":"n/a","vendor":"n/a","versions":[{"status":"affected","version":"n/a"}],"defaultStatus":null}],"fixed_versions":[],"cvss":9.8,"severity":"Critical","kev":{"listed":true,"date_added":"2021-11-03","due_date":"2021-11-17","required_action":"Apply updates per vendor instructions.","ransomware_campaign_use":"Known"},"epss":{"probability":0.9896,"percentile":0.9993,"score_date":"2026-10-23"},"published_at":"2021-09-07T16:06:58.000Z","modified_at":"2025-10-21T23:25:35.374Z","provenance":[{"source":"CISA KEV","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23T17:00:09.9001Z"},{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2021-40539","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2025-10-21T23:25:35.374Z"},{"source":"Metasploit","url":"https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/windows/http/manageengine_adselfservice_plus_cve_2021_40539.rb","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2021-09-07"},{"source":"Nuclei","url":"https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2021/CVE-2021-40539.yaml","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":null},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2021-40539","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CISA KEV","CVE List","Metasploit","Nuclei","EPSS"],"references":[{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-40539","source":"CISA KEV"},{"source":"CVE List","url":"https://www.manageengine.com","tags":["x_refsource_MISC","x_transferred"]},{"source":"CVE List","url":"https://www.manageengine.com/products/self-service-password/kb/how-to-fix-authentication-bypass-vulnerability-in-REST-API.html","tags":["x_refsource_MISC","x_transferred"]},{"source":"CVE List","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-40539","tags":["government-resource"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CISA ADP","ssvc":{"exploitation":"active","automatable":"yes","technical_impact":"total","assessed_at":"2025-02-03T14:10:08.314401Z"},"exploits":[{"source":"Metasploit","kind":"Exploit module","name":"ManageEngine ADSelfService Plus CVE-2021-40539","url":"https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/windows/http/manageengine_adselfservice_plus_cve_2021_40539.rb","date":"2021-09-07","added":"2021-11-24","check":true},{"source":"Nuclei","kind":"Scanner template","name":"Zoho ManageEngine ADSelfService Plus v6113 - Unauthenticated Remote Command Execution","url":"https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2021/CVE-2021-40539.yaml"}],"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2025-10-21T23:25:35.374Z","content_hash":"8c1b61a80a0da2631a42b3f3670e598eb30d46ea78c41ff2e18540d4bdf1327a"}}