CVE-2026-34909
Ubiquiti UniFi OS Path Traversal Vulnerability
Does this matter?
Known to be exploited in the wild (CISA KEV, CISA remediation deadline 26 June 2026). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.
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.
- CVSS 3.1
- 10.0 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
- EPSS
- 65.04% probability · 99th percentile
- CISA KEV
- Listed 23 June 2026 · due 26 June 2026
- Weakness
- CWE-22
- Affected
- ui/unifi os server · ui/unifi cloud gateway industrial firmware · ui/unifi dream machine firmware · ui/unifi dream machine pro firmware · ui/unifi dream machine special edition firmware · ui/unifi dream machine pro max firmware · ui/enterprise fortress gateway firmware · ui/unifi dream wall firmware · ui/unifi dream router firmware · ui/unifi dream router 7 firmware · ui/unifi express 7 firmware · ui/unifi network video recorder firmware · ui/unifi network video recorder pro firmware · ui/unifi network video recorder instant firmware · ui/enterprise network video recorder firmware · ui/unifi cloud gateway ultra firmware · ui/unifi cloud gateway max firmware · ui/unifi cloud gateway fiber firmware · ui/unifi dream router 5g max firmware · ui/enterprise network video recorder core firmware · +12 more
- Source
- support@hackerone.com
CISA notes
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. https://community.ui.com/releases/Security-Advisory-Bulletin-064-064/84811c09-4cf4-42ab-bd61-cc994445963b ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-34909
References
- https://community.ui.com/releases/Security-Advisory-Bulletin-064-064/84811c09-4cf4-42ab-bd61-cc994445963bPatch, Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-34909US Government Resource
- https://www.pwndefend.com/2026/06/09/cve-2026-34910-exploitation-itw-building-a-botnet-mirai/Exploit, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.