CVE-2026-34909
10.0 · CRITICAL Actively ExploitedOverview
CVE-2026-34909 is a critical-severity vulnerability affecting ui unifi_os_server. It was published on May 22, 2026 and has a CVSS 3.1 base score of 10.0 (CRITICAL). This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog, indicating active exploitation in the wild.
This vulnerability has a CVSS 3.1 base score of 10.0, rated CRITICAL. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical 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.
Remediation
Check the references section for vendor advisories and patches from ui. Update unifi_os_server to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| ui | unifi_os_server | >= 0, < 5.0.8 | Affected |
| ui | unifi_cloud_gateway_industrial_firmware | >= 0, < 5.1.12 | Affected |
| ui | unifi_dream_machine_firmware | >= 0, < 5.1.12 | Affected |
| ui | unifi_dream_machine_pro_firmware | >= 0, < 5.1.12 | Affected |
| ui | unifi_dream_machine_special_edition_firmware | >= 0, < 5.1.12 | Affected |
| ui | unifi_dream_machine_pro_max_firmware | >= 0, < 5.1.12 | Affected |
| ui | enterprise_fortress_gateway_firmware | >= 0, < 5.1.12 | Affected |
| ui | unifi_dream_wall_firmware | >= 0, < 5.1.12 | Affected |
| ui | unifi_dream_router_firmware | >= 0, < 5.1.12 | Affected |
| ui | unifi_dream_router_7_firmware | >= 0, < 5.1.12 | Affected |
| ui | unifi_express_7_firmware | >= 0, < 5.1.12 | Affected |
Frequently Asked Questions
What is CVE-2026-34909?
CVE-2026-34909 is a critical-severity vulnerability affecting ui unifi_os_server. It was published on May 22, 2026 and has a CVSS 3.1 base score of 10.0 (CRITICAL). This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog, indicating active exploitation in the wild.
How severe is CVE-2026-34909?
This vulnerability has a CVSS 3.1 base score of 10.0, rated CRITICAL. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-34909?
Check the references section for vendor advisories and patches from ui. Update unifi_os_server to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-34909?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-34909 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
Automated penetration testing that runs continuously, not just quarterly.
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Browser-based exploitation validates findings with real proof-of-concept.
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