CVE-2021-33820
CVSS v3
7.5
HIGH
EPSS Score
1.9 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
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.
Technical details
- Published
- 2021-06-18
Frequently asked questions
What is CVE-2021-33820?
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.
Is CVE-2021-33820 actively exploited?
Active exploitation of CVE-2021-33820 has not been confirmed. Its EPSS score was 1.9% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-33820?
CVE-2021-33820 has a CVSS v3 base score of 7.5 (HIGH severity).
Is CVE-2021-33820 affecting your environment?
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