---
id: "CVE-2026-34909"
kind: "vulnerability"
aliases: ["CVE-2026-34909"]
title: "A malicious actor with access to the network could exploit a Path Traversal vulnerability found in UniFi OS devices\u2026"
severity: "critical"
cvss: 10.0
epss: null
exploited: true
status: "open"
category: "infrastructure"
products: [{"name": "Ubiquiti UniFi OS", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "ui unifi os server", "fixed": ["5.0.8"], "affected": "< 5.0.8", "ecosystem": "vendor"}, {"name": "ui unifi cloud gateway industrial firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui unifi dream machine firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui unifi dream machine pro firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui unifi dream machine special edition firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui unifi dream machine pro max firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui enterprise fortress gateway firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui unifi dream wall firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui unifi dream router firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui unifi dream router 7 firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui unifi express 7 firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui unifi network video recorder firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui unifi network video recorder pro firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui unifi network video recorder instant firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui enterprise network video recorder firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui unifi cloud gateway ultra firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui unifi cloud gateway max firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui unifi cloud gateway fiber firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui unifi dream router 5g max firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui enterprise network video recorder core firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui unifi cloud key plus firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui unifi cloudkey firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui unifi cloudkey enterprise firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui unifi network video recorder g2 firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui unifi network video recorder g2 pro firmware", "fixed": ["5.1.12"], "affected": "< 5.1.12", "ecosystem": "vendor"}, {"name": "ui unifi dream machine beast firmware", "fixed": ["5.1.11"], "affected": "< 5.1.11", "ecosystem": "vendor"}, {"name": "ui unas 2 firmware", "fixed": ["5.1.10"], "affected": "< 5.1.10", "ecosystem": "vendor"}, {"name": "ui unas 4 firmware", "fixed": ["5.1.10"], "affected": "< 5.1.10", "ecosystem": "vendor"}, {"name": "ui unas pro firmware", "fixed": ["5.1.10"], "affected": "< 5.1.10", "ecosystem": "vendor"}, {"name": "ui unas pro 4 firmware", "fixed": ["5.1.10"], "affected": "< 5.1.10", "ecosystem": "vendor"}, {"name": "ui unas pro 8 firmware", "fixed": ["5.1.10"], "affected": "< 5.1.10", "ecosystem": "vendor"}, {"name": "ui unifi express firmware", "fixed": ["4.0.14"], "affected": "< 4.0.14", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["exploited", "infrastructure", "network-gear", "self-hosted", "ubiquiti", "unifi-os"]
not_affected_if: ["unknown"]
published_at: "2026-05-22T02:16:34+00:00"
first_seen_at: "2026-10-23T19:11:51+00:00"
updated_at: "2026-10-23T23:44:51+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2026-34909", "first_seen_at": "2026-10-23T19:11:51+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-34909", "first_seen_at": "2026-10-23T23:44:51+00:00"}]
---

# A malicious actor with access to the network could exploit a Path Traversal vulnerability found in UniFi OS devices…

Ubiquiti UniFi OS contains a path traversal flaw that lets an attacker with network access read files on the underlying system. Those files can be manipulated to reach an underlying account.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:Ubiquiti UniFi OS affected ? fixed ?
- vendor:ui unifi os server affected < 5.0.8 fixed 5.0.8
- vendor:ui unifi cloud gateway industrial firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui unifi dream machine firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui unifi dream machine pro firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui unifi dream machine special edition firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui unifi dream machine pro max firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui enterprise fortress gateway firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui unifi dream wall firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui unifi dream router firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui unifi dream router 7 firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui unifi express 7 firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui unifi network video recorder firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui unifi network video recorder pro firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui unifi network video recorder instant firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui enterprise network video recorder firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui unifi cloud gateway ultra firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui unifi cloud gateway max firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui unifi cloud gateway fiber firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui unifi dream router 5g max firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui enterprise network video recorder core firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui unifi cloud key plus firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui unifi cloudkey firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui unifi cloudkey enterprise firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui unifi network video recorder g2 firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui unifi network video recorder g2 pro firmware affected < 5.1.12 fixed 5.1.12
- vendor:ui unifi dream machine beast firmware affected < 5.1.11 fixed 5.1.11
- vendor:ui unas 2 firmware affected < 5.1.10 fixed 5.1.10
- vendor:ui unas 4 firmware affected < 5.1.10 fixed 5.1.10
- vendor:ui unas pro firmware affected < 5.1.10 fixed 5.1.10
- vendor:ui unas pro 4 firmware affected < 5.1.10 fixed 5.1.10
- vendor:ui unas pro 8 firmware affected < 5.1.10 fixed 5.1.10
- vendor:ui unifi express firmware affected < 4.0.14 fixed 4.0.14

## Fix

Apply the vendor mitigations or patch per Ubiquiti's advisory; if no mitigation exists, discontinue use of the affected product per CISA BOD 26-04 guidance.

## Timeline

- 2026-10-23T19:11:51+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2026-34909
- 2026-10-23T23:44:51+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-34909

## From the sources

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 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.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_