Path Traversal in UniFi OS (UniFi Devices)
CVE-2026-34909 Published on May 22, 2026
A malicious actor with access to the network could exploit a Path Traversal vulnerability found in UniFi OS devices to access files on the underlying system that could be manipulated to access an underlying account.
Known Exploited Vulnerability
This Ubiquiti UniFi OS Path Traversal Vulnerability is part of CISA's list of Known Exploited Vulnerabilities. Ubiquiti UniFi OS contains a path traversal vulnerability which could allow a malicious actor with access to the network to access files on the underlying system that could be manipulated to access an underlying account.
The following remediation steps are recommended / required by June 26, 2026: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicab
Weakness Type
What is a Directory traversal Vulnerability?
The software uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the software does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.
CVE-2026-34909 has been classified to as a Directory traversal vulnerability or weakness.
Affected Versions
Ubiquiti Inc UniFi OS Server:- Before 5.0.8 is affected.
- Before 4.0.14 is affected.
- Before 5.1.12 is affected.
- Before 5.1.12 is affected.
- Before 5.1.12 is affected.
- Before 5.1.12 is affected.
- Before 5.1.11 is affected.
- Before 5.1.12 is affected.
- Before 5.1.12 is affected.
- Before 5.1.12 is affected.
- Before 5.1.12 is affected.
- Before 5.1.12 is affected.
- Before 5.1.12 is affected.
- Before 5.1.12 is affected.
- Before 5.1.12 is affected.
- Before 5.1.12 is affected.
- Before 5.1.12 is affected.
- Before 5.1.12 is affected.
- Before 5.1.12 is affected.
- Before 5.1.12 is affected.
- Before 5.1.10 is affected.
- Before 5.1.10 is affected.
- Before 5.1.10 is affected.
- Before 5.1.10 is affected.
- Before 5.1.10 is affected.
- Before 5.1.12 is affected.
- Before 5.1.12 is affected.
- Before 5.1.12 is affected.
- Before 5.1.12 is affected.
- Before 5.1.12 is affected.
- Before 5.1.12 is affected.
- Before 5.1.12 is affected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.