CVE-2026-34909

Ubiquiti UniFi OS: Path Traversal

As of , CVE-2026-34909 in Ubiquiti UniFi OS is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch soon.

Exploited
Yes: CISA listed it on 23 June 2026
US federal deadline
26 June 20263 days after CISA listed it. US federal civilian agencies must fix it by then.
Used in ransomware campaigns
Not known to CISA
EPSS score
0.02Higher than 77% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
Public exploit
None foundNeither Metasploit nor Exploit-DB lists one.
Fix
Vendor advice: community.ui.comLinks below, from CISA's entry.

What CISA says to do

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.

CISA's required action

What the flaw is

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.

CISA's description

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.

The CVE record's description, from hackerone

CVE published
22 May 2026
Assigned by
hackerone
CVSS
10.0 Critical (CVSS 3.1, from the CNA)
CWE-22
Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CISA SSVC, exploitation
active
CISA SSVC, automatable
yes
CISA SSVC, technical impact
total

Timeline

  1. The CVE record was published.
  2. CISA added it to its list of exploited vulnerabilities.
  3. The US federal deadline to fix it.

UniFi OS: other exploited entries

VulnerabilityProductOur groupListedDeadlineEPSS
CVE-2026-34910Improper Input ValidationUbiquiti UniFi OSPatch soon0.46
CVE-2026-34908Improper Access ControlUbiquiti UniFi OSPatch soon0.15

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