{"id":"CVE-2021-20023","title":"SonicWall Email Security version 10.0.9.x contains a vulnerability that allows a post-authenticated attacker to read an arbitrary file on the remote host.","summary":"SonicWall Email Security version 10.0.9.x contains a vulnerability that allows a post-authenticated attacker to read an arbitrary file on the remote host.","severity":"medium","cvss":4.9,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N","cwe":["CWE-22","CWE-22"],"vendor":"sonicwall","product":"email_security","affected":["email_security < 10.0.9.6173","email_security_appliance_9000_firmware < 10.0.9.6177","email_security_appliance_3300_firmware < 10.0.9.6177","email_security_appliance_4300_firmware < 10.0.9.6177","email_security_appliance_8300_firmware < 10.0.9.6177","email_security_appliance_5000_firmware < 10.0.9.6177","email_security_appliance_7000_firmware < 10.0.9.6177","email_security_appliance_5050_firmware < 10.0.9.6177","email_security_appliance_7050_firmware < 10.0.9.6177","email_security_virtual_appliance < 10.0.9.6177","hosted_email_security < 10.0.9.6173"],"patched":["email_security 10.0.9.6173","email_security_appliance_9000_firmware 10.0.9.6177","email_security_appliance_3300_firmware 10.0.9.6177","email_security_appliance_4300_firmware 10.0.9.6177","email_security_appliance_8300_firmware 10.0.9.6177","email_security_appliance_5000_firmware 10.0.9.6177","email_security_appliance_7000_firmware 10.0.9.6177","email_security_appliance_5050_firmware 10.0.9.6177","email_security_appliance_7050_firmware 10.0.9.6177","email_security_virtual_appliance 10.0.9.6177","hosted_email_security 10.0.9.6173"],"published":"2021-04-20","updated":"2026-08-12","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2021-20023","references":[{"url":"https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0010","label":"PSIRT@sonicwall.com"},{"url":"https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0010","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-20023","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"tags":["nvd","kev","in-the-wild"],"epss":0.51407,"epssPercentile":0.98919,"kev":true,"kevDateAdded":"2021-11-03","kevDueDate":"2021-11-17","kevRansomware":true,"exploited":true,"zeroDay":true,"ingestedAt":"2026-08-12T19:54:25.950Z","slug":"CVE-2021-20023","body":"## Overview\n\nSonicWall Email Security version 10.0.9.x contains a vulnerability that allows a post-authenticated attacker to read an arbitrary file on the remote host.\n\n## Affected\n\n- `email_security < 10.0.9.6173`\n- `email_security_appliance_9000_firmware < 10.0.9.6177`\n- `email_security_appliance_3300_firmware < 10.0.9.6177`\n- `email_security_appliance_4300_firmware < 10.0.9.6177`\n- `email_security_appliance_8300_firmware < 10.0.9.6177`\n- `email_security_appliance_5000_firmware < 10.0.9.6177`\n- `email_security_appliance_7000_firmware < 10.0.9.6177`\n- `email_security_appliance_5050_firmware < 10.0.9.6177`\n- `email_security_appliance_7050_firmware < 10.0.9.6177`\n- `email_security_virtual_appliance < 10.0.9.6177`\n- `hosted_email_security < 10.0.9.6173`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `email_security 10.0.9.6173`\n- `email_security_appliance_9000_firmware 10.0.9.6177`\n- `email_security_appliance_3300_firmware 10.0.9.6177`\n- `email_security_appliance_4300_firmware 10.0.9.6177`\n- `email_security_appliance_8300_firmware 10.0.9.6177`\n- `email_security_appliance_5000_firmware 10.0.9.6177`\n- `email_security_appliance_7000_firmware 10.0.9.6177`\n- `email_security_appliance_5050_firmware 10.0.9.6177`\n- `email_security_appliance_7050_firmware 10.0.9.6177`\n- `email_security_virtual_appliance 10.0.9.6177`\n- `hosted_email_security 10.0.9.6173`","depth":"midnight","depthScore":67,"depthScoreParts":{"impact":27,"likelihood":10.3,"exploitation":25,"ransomware":5},"changes":[]}