CVE-2026-34909
KEVUbiquiti UniFi OS Path Traversal Vulnerability
Description
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.
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.
CVSS 3.1 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:HPublishedMay 22, 2026
Last modifiedJul 23, 2026
Added to KEVJun 23, 2026
Remediation dueJun 26, 2026
References
- community.ui.com/releases/Security-Advisory-Bulletin-064-064/84811c09-4cf4-42ab-bd61-cc994445963bPatchVendor Advisory
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-34909US Government Resource
- pwndefend.com/2026/06/09/cve-2026-34910-exploitation-itw-building-a-botnet-mirai/ExploitThird Party Advisory
0 recent articles mention this CVE
87
Risk assessment · Critical
Actively exploited. Patch immediately.
- Exploitation
- Confirmed in the wild (CISA KEV)
- Federal remediation deadline
- Overdue by 122 days
- CVSS
- 10.0 CRITICAL
- EPSS (30-day exploit probability)
- 68.0% · top 1% of all CVEs
- Weakness
- CWE-22
- Attack vector
- Network, remotely reachable
- Preconditions
- No privileges and no user interaction
Recommended actions
- 1.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.
- 2.Treat as emergency change: patch or isolate internet-facing instances first.
- 3.Review exposure: confirm which instances are reachable from the internet and restrict access until patched.
- 4.Hunt for compromise: review logs for the disclosure window, not just from the patch date.
Assessment is derived automatically from the live signals above; verify against your own asset inventory.