CVE-2026-77556 - Vulnerability Details - OpenCVE

A malicious actor with access to the network could exploit an Out-of-bounds Read 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.

No EPSS score available.

Exploitation none

Automatable yes

Technical Impact partial

No data.

No data.

No data.

OpenCVE Enrichment is a feature of OpenCVE that uses AI to automatically link vendors and products to CVEs. Learn more on GitHub.

No data.

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

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

History

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 20:15:00 +0000

Type	Values Removed	Values Added
Title		Out-of-Bounds Read Exploitation Causing Denial of Service on UniFi Gateways

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 Read vulnerability found in certain UniFi gateway devices to execute a Denial of Service (DoS) attack on the device.
Weaknesses		CWE-125
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'}`

Projects

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MITRE

Status: PUBLISHED

Assigner: Ubiquiti

Published: 2026-09-22T18:41:15.201Z

Updated: 2026-09-22T19:33:21.537Z

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

Link: CVE-2026-77556

Vulnrichment

Updated: 2026-09-22T19:33:17.773Z

NVD

Status : Deferred

Published: 2026-09-22T19:16:51.860

Modified: 2026-09-22T20:17:08.570

Link: CVE-2026-77556

Redhat

No data.

OpenCVE Enrichment

Updated: 2026-09-22T20:00:13Z

Weaknesses

CWE-125

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