CVE-2026-34909Ubiquiti UniFi OS Path Traversal Vulnerability
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.
Overview
Severity
| Score | Severity | Version | Vector String |
|---|---|---|---|
| 10.0 | CRITICAL | 3.1hackerone (CNA) | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
CISA required action
⚡ Known exploited · remediation due Jun 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 applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Details
- CVE ID
- CVE-2026-34909
- Status
- Analyzed
- Assigner (CNA)
- hackerone
- Published
- May 22, 2026
- Last modified
- 2026-07-23 16:10 UTC
- Weaknesses
- CWE-22 · Path Traversal
Affected Products
As published by the CNA in the CVE record.
Ubiquiti IncUniFi OS Server1 version range
- before 5.0.8
Ubiquiti IncExpress1 version range
- before 4.0.14
Ubiquiti IncUDM1 version range
- before 5.1.12
Ubiquiti IncUDM-Pro1 version range
- before 5.1.12
Ubiquiti IncUDM-SE1 version range
- before 5.1.12
Ubiquiti IncUDM-Pro-Max1 version range
- before 5.1.12
Ubiquiti IncUDM-Beast1 version range
- before 5.1.11
Ubiquiti IncEFG1 version range
- before 5.1.12
Ubiquiti IncUDW1 version range
- before 5.1.12
Ubiquiti IncUDR1 version range
- before 5.1.12
Ubiquiti IncUDR71 version range
- before 5.1.12
Ubiquiti IncUDR-5G1 version range
- before 5.1.12
Ubiquiti IncExpress 71 version range
- before 5.1.12
Ubiquiti IncUNVR1 version range
- before 5.1.12
Ubiquiti IncUNVR-Pro1 version range
- before 5.1.12
Ubiquiti IncUNVR-Instant1 version range
- before 5.1.12
Ubiquiti IncUNVR-G21 version range
- before 5.1.12
Ubiquiti IncUNVR-G2-Pro1 version range
- before 5.1.12
Ubiquiti IncENVR1 version range
- before 5.1.12
Ubiquiti IncENVR-Core1 version range
- before 5.1.12
Ubiquiti IncUNAS-21 version range
- before 5.1.10
Ubiquiti IncUNAS-41 version range
- before 5.1.10
Ubiquiti IncUNAS-Pro1 version range
- before 5.1.10
Ubiquiti IncUNAS-Pro-41 version range
- before 5.1.10
Ubiquiti IncUNAS-Pro-81 version range
- before 5.1.10
Ubiquiti IncUCKP1 version range
- before 5.1.12
Ubiquiti IncUCK1 version range
- before 5.1.12
Ubiquiti IncUCK-Enterprise1 version range
- before 5.1.12
Ubiquiti IncUCG-Ultra1 version range
- before 5.1.12
Ubiquiti IncUCG-Max1 version range
- before 5.1.12
Ubiquiti IncUCG-Fiber1 version range
- before 5.1.12
Ubiquiti IncUCG-Industrial1 version range
- before 5.1.12
References
- community.ui.com https://community.ui.com/releases/Security-Advisory-Bulletin-064-064/84811c09-4cf4-42ab-bd61-cc994445963b
- cisa.gov https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-34909
- pwndefend.com https://www.pwndefend.com/2026/06/09/cve-2026-34910-exploitation-itw-building-a-botnet-mirai/