Path Traversal in Ubiquiti UniFi OS Authentication Gateway
CVE-2026-34909 is a path traversal vulnerability affecting Ubiquiti UniFi OS devices, including UniFi OS Server. A network-accessible attacker can exploit the flaw to traverse directories and access files on the underlying operating system. Available reporting indicates the issue is in the UniFi OS authentication gateway and can expose sensitive files from the host system. Bishop Fox reported that, in practice, CVE-2026-34909 can be combined with CVE-2026-34908 to bypass authentication and reach internal protected endpoints due to differences between raw URI validation and normalized URI routing in the request handling path. The vendor and third-party reporting further state that accessed files may be manipulated or leveraged to obtain access to an underlying system account, making the flaw more than a simple file-read issue when used in an attack chain.
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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
22 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
A path traversal vulnerability in Ubiquiti UniFi OS Server that can be chained with CVE-2026-34908 and CVE-2026-34910 to achieve unauthenticated remote code execution with root privileges.
A path traversal vulnerability in Ubiquiti UniFi OS Server that helps enable authentication bypass as part of a chained unauthenticated root RCE attack.
A path traversal flaw in the UniFi OS authentication gateway caused by divergence between raw and normalized URI handling, enabling authentication bypass when chained with related flaws.
A maximum severity UniFi OS path traversal vulnerability that allows remote attackers without privileges to access underlying system files.
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Every observed campaign linking this CVE to a named adversary.
Malware families riding this exploit, with evidence and IOCs.
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Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.