{"id":"CVE-2021-20038","aliases":["EUVD-2021-7501","GHSA-jmhc-vxg9-h2g4"],"status":"published","title":"A Stack-based buffer overflow vulnerability in SMA100 Apache httpd server's mod_cgi module...","description":"A Stack-based buffer overflow vulnerability in SMA100 Apache httpd server's mod_cgi module environment variables allows a remote unauthenticated attacker to potentially execute code as a 'nobody' user in the appliance. This vulnerability affected SMA 200, 210, 400, 410 and 500v appliances firmware 10.2.0.8-37sv, 10.2.1.1-19sv, 10.2.1.2-24sv and earlier versions.","severity":{"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":"primary","from":"nvd"},"epss":{"day":"2026-11-11","score":0.99912,"percentile":0.99967,"model":"v2026.06.15"},"facts":{"in_kev":true,"known_exploited":true,"public_exploit":true,"fix_available":false},"cwes":["CWE-121","CWE-787"],"published":"2021-12-08T09:55:20Z","modified":"2026-06-17T03:33:11Z","kev":{"date_added":"2022-01-28","due_date":"2022-02-11","required_action":"Apply updates per vendor instructions.","known_ransomware_use":"Known"},"exploitation":[{"source":"euvd","since":"2022-01-28"},{"source":"kev","since":"2022-01-28"}],"exploits":[{"source":"metasploit","id":"exploit/linux/http/sonicwall_cve_2021_20039","title":"SonicWall SMA 100 Series Authenticated Command Injection","type":"exploit","platform":"Linux","date":"2021-12-14","verified":true,"url":"https://www.rapid7.com/db/modules/exploit/linux/http/sonicwall_cve_2021_20039"},{"source":"pocgithub","id":"jbaines-r7/badblood","title":"jbaines-r7/badblood","date":"2022-01-11","url":"https://github.com/jbaines-r7/badblood"},{"source":"pocgithub","id":"vesperp/CVE-2021-20038-SonicWall-RCE","title":"vesperp/CVE-2021-20038-SonicWall-RCE","date":"2022-08-08","url":"https://github.com/vesperp/CVE-2021-20038-SonicWall-RCE"},{"source":"pocgithub","id":"anir0y/sonicwall-audit-toolkit","title":"anir0y/sonicwall-audit-toolkit","date":"2026-02-23","url":"https://github.com/anir0y/sonicwall-audit-toolkit"},{"source":"nuclei","id":"CVE-2021-20038","title":"SonicWall SMA100 Stack - Buffer Overflow/Remote Code Execution","type":"detection template","url":"https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2021/CVE-2021-20038.yaml"}],"products":[{"vendor":"sonicwall","product":"sma 100 appliances"},{"vendor":"sonicwall","product":"sma_200_firmware"},{"vendor":"sonicwall","product":"sma_210_firmware"},{"vendor":"sonicwall","product":"sma_400_firmware"},{"vendor":"sonicwall","product":"sma_410_firmware"},{"vendor":"sonicwall","product":"sma_500v_firmware"},{"vendor":"sonicwall","product":"sonicwall sma100"}],"references":[{"url":"https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0026","tags":["x_refsource_CONFIRM","x_transferred","Vendor Advisory"]},{"url":"https://github.com/jbaines-r7/badblood","tags":["x_refsource_MISC","x_transferred","Exploit","Third Party Advisory"]},{"url":"https://www.rapid7.com/blog/post/2022/01/11/cve-2021-20038-42-sonicwall-sma-100-multiple-vulnerabilities-fixed-2/","tags":["x_refsource_MISC","x_transferred","Exploit","Third Party Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-20038","tags":["government-resource","US Government Resource"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-20038"},{"url":"https://www.rapid7.com/blog/post/2022/01/11/cve-2021-20038-42-sonicwall-sma-100-multiple-vulnerabilities-fixed-2"},{"url":"https://github.com/advisories/GHSA-jmhc-vxg9-h2g4"}],"sources":{"cve":[{"id":"CVE-2021-20038","description":"A Stack-based buffer overflow vulnerability in SMA100 Apache httpd server's mod_cgi module environment variables allows a remote unauthenticated attacker to potentially execute code as a 'nobody' user in the appliance. This vulnerability affected SMA 200, 210, 400, 410 and 500v appliances firmware 10.2.0.8-37sv, 10.2.1.1-19sv, 10.2.1.2-24sv and earlier versions.","status":"published","published":"2021-12-08T09:55:20Z","modified":"2025-10-21T23:25:23.415Z","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","assessor":"adp"}],"cwes":["CWE-121"],"updated_at":"2026-11-02T14:32:55.19484Z"}],"euvd":[{"id":"EUVD-2021-7501","description":"A Stack-based buffer overflow vulnerability in SMA100 Apache httpd server's mod_cgi module environment variables allows a remote unauthenticated attacker to potentially execute code as a 'nobody' user in the appliance. This vulnerability affected SMA 200, 210, 400, 410 and 500v appliances firmware 10.2.0.8-37sv, 10.2.1.1-19sv, 10.2.1.2-24sv and earlier versions.","status":"published","published":"2021-12-08T09:55:20Z","modified":"2025-10-21T23:25:23Z","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"}],"exploited_since":"2022-01-28","updated_at":"2026-11-02T20:31:25.901288Z"}],"ghsa":[{"id":"GHSA-jmhc-vxg9-h2g4","title":"A Stack-based buffer overflow vulnerability in SMA100 Apache httpd server's mod_cgi module...","description":"A Stack-based buffer overflow vulnerability in SMA100 Apache httpd server's mod_cgi module environment variables allows a remote unauthenticated attacker to potentially execute code as a 'nobody' user in the appliance. This vulnerability affected SMA 200, 210, 400, 410 and 500v appliances firmware 10.2.0.8-37sv, 10.2.1.1-19sv, 10.2.1.2-24sv and earlier versions.","status":"published","published":"2021-12-09T00:01:13Z","modified":"2025-10-22T00:33:31Z","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-121","CWE-787"],"updated_at":"2026-11-02T15:04:08.198655Z"}],"kev":[{"id":"CVE-2021-20038","title":"SonicWall SMA 100 Appliances Stack-Based Buffer Overflow Vulnerability","description":"SonicWall SMA 100 devies are vulnerable to an unauthenticated stack-based buffer overflow vulnerability where exploitation can result in code execution.","cwes":["CWE-121"],"kev":{"date_added":"2022-01-28","due_date":"2022-02-11","required_action":"Apply updates per vendor instructions.","known_ransomware_use":"Known"},"updated_at":"2026-11-02T17:00:16.541131Z"}],"nvd":[{"id":"CVE-2021-20038","description":"A Stack-based buffer overflow vulnerability in SMA100 Apache httpd server's mod_cgi module environment variables allows a remote unauthenticated attacker to potentially execute code as a 'nobody' user in the appliance. This vulnerability affected SMA 200, 210, 400, 410 and 500v appliances firmware 10.2.0.8-37sv, 10.2.1.1-19sv, 10.2.1.2-24sv and earlier versions.","status":"published","published":"2021-12-08T10:15:07.75Z","modified":"2026-06-17T03:33:11.327Z","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","assessor":"primary"},{"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":7.5,"vector":"AV:N/AC:L/Au:N/C:P/I:P/A:P","level":"high","assessor":"primary"}],"cwes":["CWE-121","CWE-787"],"updated_at":"2026-11-02T14:07:01.811115Z"}]}}