Path Traversal in Ubiquiti Inc Efg
CVE-2026-34909
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.
Vulnerability class: Path Traversal (Directory Traversal)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 10.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.018 (78.1th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 78th percentile — 78.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.650 · newest: 0.018 · change: -0.633
Affected products
- Ubiquiti Inc Efg — versions 0
- Ubiquiti Inc Envr — versions 0
- Ubiquiti Inc Envr-Core — versions 0
- Ubiquiti Inc Express — versions 0
- Ubiquiti Inc Express 7 — versions 0
- Ubiquiti Inc Ucg-Fiber — versions 0
- Ubiquiti Inc Ucg-Industrial — versions 0
- Ubiquiti Inc Ucg-Max — versions 0
- Ubiquiti Inc Ucg-Ultra — versions 0
- Ubiquiti Inc Uck — versions 0
Weakness classification (CWE)
CISA KEV (Known Exploited Vulnerabilities)
This CVE is on the CISA KEV catalog, added on . CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.
BOD 22-01 due date: .
Required action: 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.
References
- community.ui.com/releases/Security-Advisory-Bulletin-064-064/84811c09-4cf4-42ab… (Patch, Vendor Advisory)
- 134c704f-9b21-4f2e-91b3-4a467353bcc0 (US Government Resource)
- 134c704f-9b21-4f2e-91b3-4a467353bcc0 (Exploit, Third Party Advisory)
Frequently asked questions
- What is CVE-2026-34909?
- CVE-2026-34909 is a critical-severity vulnerability in Ubiquiti Inc Efg, classified under Path Traversal. CVSS score: 10.0/10. Published 2026-05-22.
- How severe is CVE-2026-34909?
- Critical severity. CVSS v3 base score is 10.0 out of 10.
- Is CVE-2026-34909 known to be exploited?
- Yes. CVE-2026-34909 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2026-06-23), indicating it is being actively exploited.