{"id":"CVE-2021-33820","aliases":["EUVD-2021-20495","GHSA-8vw7-3cp3-ph8j"],"status":"published","title":"An issue was discovered in UniFi Protect G3 FLEX Camera Version UVC.v4.30.0.67.Attacker could...","description":"An issue was discovered in UniFi Protect G3 FLEX Camera Version UVC.v4.30.0.67.Attacker could send a huge amount of TCP SYN packet to make web service's resource exhausted. Then the web server is denial-of-service.","severity":{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-11","score":0.01934,"percentile":0.80321,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-400"],"published":"2021-06-18T18:32:04Z","modified":"2026-06-17T03:55:16Z","products":[{"vendor":"ui","product":"camera_g3_flex_firmware"}],"references":[{"url":"https://store.ui.com/collections/unifi-protect-cameras/products/unifi-video-g3-flex-camera","tags":["x_refsource_MISC","x_transferred","Product","Vendor Advisory"]},{"url":"https://linuxhint.com/hping3/","tags":["x_refsource_MISC","x_transferred","Third Party Advisory"]},{"url":"https://github.com/Jian-Xian/CVE-POC/blob/master/CVE-2021-33820.md","tags":["x_refsource_MISC","x_transferred","Exploit","Third Party Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-33820"},{"url":"https://github.com/advisories/GHSA-8vw7-3cp3-ph8j"}],"sources":{"cve":[{"id":"CVE-2021-33820","description":"An issue was discovered in UniFi Protect G3 FLEX Camera Version UVC.v4.30.0.67.Attacker could send a huge amount of TCP SYN packet to make web service's resource exhausted. Then the web server is denial-of-service.","status":"published","published":"2021-06-18T18:32:04Z","modified":"2024-08-03T23:58:23.227Z","updated_at":"2026-11-02T14:33:10.204494Z"}],"euvd":[{"id":"EUVD-2021-20495","description":"An issue was discovered in UniFi Protect G3 FLEX Camera Version UVC.v4.30.0.67.Attacker could send a huge amount of TCP SYN packet to make web service's resource exhausted. Then the web server is denial-of-service.","status":"published","published":"2021-06-18T18:32:04Z","modified":"2024-08-03T23:58:23Z","updated_at":"2026-11-03T03:24:33.318275Z"}],"ghsa":[{"id":"GHSA-8vw7-3cp3-ph8j","title":"An issue was discovered in UniFi Protect G3 FLEX Camera Version UVC.v4.30.0.67.Attacker could...","description":"An issue was discovered in UniFi Protect G3 FLEX Camera Version UVC.v4.30.0.67.Attacker could send a huge amount of TCP SYN packet to make web service's resource exhausted. Then the web server is denial-of-service.","status":"published","published":"2022-05-24T19:05:38Z","modified":"2023-01-27T05:03:19Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"cwes":["CWE-400"],"updated_at":"2026-11-02T14:42:13.302487Z"}],"nvd":[{"id":"CVE-2021-33820","description":"An issue was discovered in UniFi Protect G3 FLEX Camera Version UVC.v4.30.0.67.Attacker could send a huge amount of TCP SYN packet to make web service's resource exhausted. Then the web server is denial-of-service.","status":"published","published":"2021-06-18T19:15:07.537Z","modified":"2026-06-17T03:55:16.233Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:N/I:N/A:P","level":"medium","assessor":"primary"}],"updated_at":"2026-11-02T14:06:54.892562Z"}]}}