SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-34908

Ubiquiti UniFi OS Improper Access Control Vulnerability

KEVCRITICAL 10.0EPSS 85.2%

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 an Improper Access Control vulnerability found in UniFi OS devices to make unauthorized changes to the system.

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
85.19% probability · 100th percentile
CISA KEV
Listed 23 June 2026 · due 26 June 2026
Weakness
CWE-284
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 · +11 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-2026-34908

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.