CVE-2026-77555 - Vulnerability Details - OpenCVE

A malicious actor with access to the network could exploit an Out-of-bounds Write vulnerability found in certain UniFi gateway devices to execute a Denial of Service (DoS) attack on the device.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation none

Automatable yes

Technical Impact partial

Vendors	Products
Ubiquiti	Cloud Gateways Dream Machines Dream Routers Dream Wall Enterprise Firewalls Express Express 7 Unifi Gateways

No data.

No data.

References

Link	Providers
https://community.ui.com/releases/Security-Advisory-Bulletin-069-069/07e367a7-edec-4d85-a058-f97e5ce9ac9c

History

Tue, 29 Sep 2026 13:30:00 +0000

Type	Values Removed	Values Added
First Time appeared		Ubiquiti Ubiquiti cloud Gateways Ubiquiti dream Machines Ubiquiti dream Routers Ubiquiti dream Wall Ubiquiti enterprise Firewalls Ubiquiti express Ubiquiti express 7 Ubiquiti unifi Gateways
Vendors & Products		Ubiquiti Ubiquiti cloud Gateways Ubiquiti dream Machines Ubiquiti dream Routers Ubiquiti dream Wall Ubiquiti enterprise Firewalls Ubiquiti express Ubiquiti express 7 Ubiquiti unifi Gateways

Tue, 22 Sep 2026 20:30:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Tue, 22 Sep 2026 18:45:00 +0000

Type	Values Removed	Values Added
Description		A malicious actor with access to the network could exploit an Out-of-bounds Write vulnerability found in certain UniFi gateway devices to execute a Denial of Service (DoS) attack on the device.
Weaknesses		CWE-787
References		https://community.ui.com/releases/Security-Advisory-Bulletin-069-069/07e367a7-edec-4d85-a058-f97e5ce9ac9c
Metrics		cvssV3_1 `{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}`

MITRE

Status: PUBLISHED

Assigner: Ubiquiti

Published: 2026-09-22T18:38:20.615Z

Updated: 2026-09-22T19:32:56.582Z

Reserved: 2026-08-20T20:32:43.655Z

Link: CVE-2026-77555

Vulnrichment

Updated: 2026-09-22T19:32:50.332Z

NVD

Status : Deferred

Published: 2026-09-22T19:16:51.737

Modified: 2026-09-22T20:17:08.460

Link: CVE-2026-77555

Redhat

No data.

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