Predictive Vulnerability Intelligence.

Product

  • Product
  • Pricing
  • Documentation

Company

  • About
  • Partnerships
  • Blog
  • Support

Legal

  • Terms
  • Privacy
  • Data Licensing

© 2026 FAUCET Technologies LLC. All rights reserved.

CVE-2021-33820

24
FAUCET Score

CVE-2021-33820 is a denial-of-service vulnerability affecting UniFi Protect G3 FLEX Cameras running firmware version UVC.v4.30.0.67. An unauthenticated attacker can exhaust the web service's resources by flooding it with TCP SYN packets, rendering the device inaccessible. This vulnerability has a CVSS score of 7.5 (High) due to its network-based attack vector and high impact on availability, with low attack complexity. There is currently no evidence of active exploitation, public exploit code, or significant community discussion surrounding this CVE.

Impacted Technologies

VendorProductVersion(s)CPE
uvc.v4.30.0.67CPE matchmatch criteria
cpe:2.3:o:ui:camera_g3_flex_firmware:uvc.v4.30.0.67:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.1

7.5HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
Exploitability Score
3.9
Impact Score
3.6
CvssVersion
3.1

Exploit Intelligence

EPSS Score
1.93%
Probability of exploitation in next 30 days
EPSS Percentile
77.9%
Percentile rank of EPSS score among Peer Group
As of 2026-07-27
Model: v2026.06.15
This CVE's current EPSS score of 0.0193 is in the 61st percentile among its peer group of 51,551 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.1 Mastodon, and 0.4 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Remediation records are not available for this CVE.

References

github.com / Jian-Xian/CVE-POC/blob/master/CVE-2021-33820.md
ExploitThird Party Advisory
linuxhint.com / hping3
Third Party Advisory
store.ui.com / collections/unifi-protect-cameras/products/unifi-video-g3-flex-camera
ProductVendor Advisory