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Remote Code Execution","type":"detection template","url":"https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2021/CVE-2021-34473.yaml"}],"products":[{"vendor":"microsoft","product":"exchange server"},{"vendor":"microsoft","product":"exchange_server"},{"vendor":"microsoft","product":"microsoft exchange server 2013 cumulative update 23"},{"vendor":"microsoft","product":"microsoft exchange server 2016 cumulative update 19"},{"vendor":"microsoft","product":"microsoft exchange server 2016 cumulative update 20"},{"vendor":"microsoft","product":"microsoft exchange server 2019 cumulative update 8"},{"vendor":"microsoft","product":"microsoft exchange server 2019 cumulative update 9"}],"references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-34473","tags":["vendor-advisory","patch","Patch","Vendor Advisory"]},{"url":"https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-34473","tags":["x_refsource_MISC","x_transferred","Patch","Vendor Advisory"]},{"url":"https://www.zerodayinitiative.com/advisories/ZDI-21-821/","tags":["x_refsource_MISC","x_transferred","Third Party Advisory","VDB Entry"]},{"url":"http://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-Remote-Code-Execution.html","tags":["x_refsource_MISC","x_transferred","Exploit","Third Party Advisory","VDB Entry"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-34473","tags":["government-resource","US Government Resource"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-34473"},{"url":"https://www.zerodayinitiative.com/advisories/ZDI-21-821"},{"url":"https://github.com/advisories/GHSA-fgq9-p33g-xcfc"}],"sources":{"cve":[{"id":"CVE-2021-34473","title":"Microsoft Exchange Server Remote Code Execution Vulnerability","description":"Microsoft Exchange Server Remote Code Execution Vulnerability","status":"published","published":"2021-07-14T17:54:03Z","modified":"2026-08-10T15:11:21.909Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N/E:U/RL:O/RC:C","level":"critical","assessor":"cna"}],"cwes":["CWE-918"],"updated_at":"2026-11-02T14:33:11.59359Z"}],"euvd":[{"id":"EUVD-2021-21128","description":"Microsoft Exchange Server Remote Code Execution Vulnerability","status":"published","published":"2021-07-14T17:54:03Z","modified":"2026-08-10T15:11:21Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N/E:U/RL:O/RC:C","level":"critical"}],"exploited_since":"2021-11-03","updated_at":"2026-11-02T18:02:04.543433Z"}],"ghsa":[{"id":"GHSA-fgq9-p33g-xcfc","title":"Microsoft Exchange Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021...","description":"Microsoft Exchange Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-31196, CVE-2021-31206.","status":"published","published":"2022-05-24T19:07:52Z","modified":"2026-08-10T18:30:39Z","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"}],"cwes":["CWE-918"],"updated_at":"2026-11-02T15:10:14.126548Z"}],"kev":[{"id":"CVE-2021-34473","title":"Microsoft Exchange Server Remote Code Execution Vulnerability","description":"Microsoft Exchange Server contains an unspecified vulnerability that allows for remote code execution.","cwes":["CWE-918"],"kev":{"date_added":"2021-11-03","due_date":"2021-11-17","required_action":"Apply updates per vendor instructions.","known_ransomware_use":"Known"},"updated_at":"2026-11-02T17:00:17.050017Z"}],"nvd":[{"id":"CVE-2021-34473","description":"Microsoft Exchange Server Remote Code Execution Vulnerability","status":"published","published":"2021-07-14T18:15:11.163Z","modified":"2026-08-10T19:58:52.8Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical","assessor":"secondary"},{"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":"secondary"},{"version":"2.0","score":10,"vector":"AV:N/AC:L/Au:N/C:C/I:C/A:C","level":"high","assessor":"primary"}],"cwes":["CWE-918"],"updated_at":"2026-11-02T14:06:55.747384Z"}]}}