How severe is CVE-2026-34909?

CVE-2026-34909 has a CVSS 3.x base score of 10.0, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-34909 being actively exploited?

Yes. CVE-2026-34909 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2026-06-23, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2026-34909?

CVE-2026-34909 primarily affects Ui Unifi Os Server. In total, 32 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-34909?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2026-34909 have an EU (EUVD) identifier?

Yes. CVE-2026-34909 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31384. It is also flagged as exploited in the EUVD (since 2026-06-23).

When was CVE-2026-34909 published?

CVE-2026-34909 was published on 2026-05-22 and last updated on 2026-07-23.

CVE-2026-34909

CVE-2026-34909 is a critical-severity vulnerability in Ui Unifi Os Server with a CVSS 3.x base score of 10.0. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2026-06-23). The underlying weakness is classified as CWE-22.

Key facts

Severity: Critical (CVSS 3.x base score 10.0)
EPSS exploit prediction: 64% (99th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2026-06-23)
EU (EUVD) id: EUVD-2026-31384
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2026-06-23)
Weakness: CWE-22
Affected product: Ui Unifi Os Server
Published: 2026-05-22
Last modified: 2026-07-23

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.

Frequently asked questions

What is 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.
How severe is CVE-2026-34909?: CVE-2026-34909 has a CVSS 3.x base score of 10.0, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-34909 being actively exploited?: Yes. CVE-2026-34909 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2026-06-23, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2026-34909?: CVE-2026-34909 primarily affects Ui Unifi Os Server. In total, 32 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-34909?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2026-34909 have an EU (EUVD) identifier?: Yes. CVE-2026-34909 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31384. It is also flagged as exploited in the EUVD (since 2026-06-23).
When was CVE-2026-34909 published?: CVE-2026-34909 was published on 2026-05-22 and last updated on 2026-07-23.

References

Affected products (32)

cpe:2.3:a:ui:unifi_os_server:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_cloud_gateway_industrial_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_dream_machine_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_dream_machine_pro_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_dream_machine_special_edition_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_dream_machine_pro_max_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:enterprise_fortress_gateway_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_dream_wall_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_dream_router_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_dream_router_7_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_express_7_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_network_video_recorder_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_network_video_recorder_pro_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_network_video_recorder_instant_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:enterprise_network_video_recorder_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_cloud_gateway_ultra_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_cloud_gateway_max_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_cloud_gateway_fiber_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_dream_router_5g_max_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:enterprise_network_video_recorder_core_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_cloud_key_plus_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_cloudkey_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_cloudkey_enterprise_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_network_video_recorder_g2_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_network_video_recorder_g2_pro_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_dream_machine_beast_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unas_2_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unas_4_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unas_pro_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unas_pro_4_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unas_pro_8_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:ui:unifi_express_firmware:*:*:*:*:*:*:*:*

More vulnerabilities in Ui Unifi Os Server

CVE-2026-34910 — Critical (CVSS 10.0): A malicious actor with access to the network could exploit an Improper Input Validation vulnerability found in UniFi OS…
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