Command Injection Vulnerability in UniFi OS Server by Ubiquiti
CVE-2026-77539

9.1CRITICAL

Key Information:

Vendor

Ubiquiti Inc

Status
Unifi Os Server
Vendor
CVE Published:
26 August 2026

What is CVE-2026-77539?

A vulnerability exists in UniFi OS Server that allows unauthorized command execution due to improper input validation. A malicious actor with network access and high privileges could exploit this vulnerability to inject arbitrary commands, potentially compromising the host device's integrity. It is crucial for administrators to implement appropriate security measures to mitigate the risk associated with this issue.

Affected Version(s)

UniFi OS Server 0 < 5.1.37

References

https://community.ui.com/releases/Security-Advisory-Bulle...

CVSS V3.1

Score:
9.1
Severity:
CRITICAL
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
High
User Interaction:
None
Scope:
Changed

Timeline

  • Vulnerability published

  • Vulnerability Reserved

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