Ubiquiti UniFi OS Improper Access Control Vulnerability
CVE-2026-34908 is a critical improper access control vulnerability in Ubiquiti UniFi OS, including UniFi OS Server. Public reporting and technical analysis indicate the flaw is part of the UniFi OS authentication gateway and can allow an attacker with network access, without authentication, to make unauthorized changes to the system. Bishop Fox reported that CVE-2026-34908 can be combined with CVE-2026-34909 due to inconsistencies between how the UniFi stack validates the raw request URI and how NGINX routes the normalized URI, enabling an authentication gateway bypass to internal routes that should require authentication. On its own, the vendor describes the issue as allowing unauthorized system changes; when chained with CVE-2026-34909 and CVE-2026-34910, it can contribute to unauthenticated remote code execution and full root compromise on vulnerable UniFi OS deployments.
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Impact, mitigation & remediation
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Impact
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Mitigation
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Remediation
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Exploits
No valid public exploits. Mallory filtered out 1 candidate as fakes, detection scripts, or README-only repos.
All candidate exploits were filtered out by Mallory's validation.
Affected products & vendors
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Recent activity
54 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
An improper access control vulnerability in Ubiquiti UniFi OS that allows an unauthenticated attacker with network access to make unauthorized system changes.
An access control bypass/authentication gateway bypass vulnerability in Ubiquiti UniFi OS that can allow unauthenticated access to protected backend services and can be chained toward privileged remote code execution.
An improper input validation vulnerability in Ubiquiti UniFi OS that can allow a malicious actor with network access to conduct command injection. It is part of a three-vulnerability RCE chain.
A critical improper access control vulnerability in Ubiquiti UniFi OS that can allow remote, unauthenticated attackers to make unauthorized changes. Patch analysis indicates it is part of an authentication gateway bypass chain involving crafted NGINX requests.
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Cross-references every affected SKU, including bundled OEM variants.
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