Medium severity · published Jan 5, 2026
CVE-2026-21634
A malicious actor with access to the adjacent network could overflow the UniFi Protect Application (Version 6.1.79 and earlier) discovery protocol causing it to restart
6.5
CVSS
0.4%
EPSS
No
On KEV
Description
A malicious actor with access to the adjacent network could overflow the UniFi Protect Application (Version 6.1.79 and earlier) discovery protocol causing it to restart.
Affected Products:
UniFi Protect Application (Version 6.1.79 and earlier).
Mitigation:
Update your UniFi Protect Application to Version 6.2.72 or later.
CVSS vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 37% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
UP
Unifi Protect · UI
before 6.2.72 · source: NVD
In the news
VulnerabilityMedium
ZDI-26-128: (Pwn2Own) Ubiquiti Networks AI Pro Uncaught Exception Denial-of-Service Vulnerability
This vulnerability allows network-adjacent attackers to create a denial-of-service condition on affected installations of Ubiquiti Networks AI Pro. Authentication is not required to exploit this vulnerability. The ZDI has assigned a CVSS rating of 6.5. The following CVEs are assigned: CVE-2026-21634.
Feb 25, 2026·Zero Day Initiative
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-21634
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-21634
Vendor Advisory
https://community.ui.com/releases/Security-Advisory-Bulletin-058-058/6922ff20-8cd7-4724-8d8c-676458a2d0f9
More from Unifi Protect
9.9
CVE-2026-55115
A malicious actor with access to the network and low privileges could exploit a Server-Side Request Forgery (SSRF) in UniFi Protect Application to escalate privileges on the host…
9.8
CVE-2026-54408
A malicious actor with access to the network could exploit an Improper Access Control vulnerability found in UniFi Protect Application to bypass authentication for data streaming
9.6
CVE-2021-22943
A vulnerability found in UniFi Protect application V1.18.1 and earlier permits a malicious actor who has already gained access to a network to subsequently control the Protect…
8.8
CVE-2026-56841
A malicious actor with access to the network and low privileges could exploit an authenticated SQL Injection vulnerability found in UniFi Protect Application to escalate…
8.8
CVE-2026-21633
A malicious actor with access to the adjacent network could obtain unauthorized access to a UniFi Protect Camera by exploiting a discovery protocol vulnerability in the Unifi…