CVE-2026-34909: Ubiquiti UniFi OS Path Traversal Vulnerability

Advisory generated from the CVE record, CISA, Exploit Observer and VEDAS: what it is, whether it is exploited, who is affected, and how to fix and detect it.

Generated by VEDAS. Scores as of 2026-11-01 19:19 UTC. Rebuilt every few hours from cve-scores, CISA KEV and vedas-signatures. How this works and its limits.

What it is

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.

Description quoted from the CVE record (assigned by hackerone, published 2026-05-22).

Weakness: CWE-22 Path Traversal

How it can be exploited

Exploitable over the network with low attack complexity needing no privileges and no user interaction. Impact: confidentiality high, integrity high, availability high. CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

CISA assessment (SSVC): CISA assesses exploitation as active. Automatable: yes. Technical impact: total.

On CISA KEV since
2026-06-23
US federal deadline
2026-06-26
Ransomware use
Not known

Public exploit evidence (Exploit Observer)

Also known as: BDU:2026-07799, EUVD-2026-31384, GHSA-95fp-244g-g3vr

Exploit Observer has no public exploit code that names this CVE or one of its aliases.

Vulnerability databases and vendor advisories (4)

Catalogue entries, not exploit evidence.

3 more references returned by Exploit Observer did not name this CVE or an alias, so they are left out.

VEDAS data as of 2026-11-01T17:12 UTC; fetched 2026-11-02.

Live scores

EPSS
0.680
very likely to be attacked soon
VEDAS
0.664
some exploit evidence
On CISA KEV
Yes, since 2026-06-23
Detection rule
None yet
EPSS (chance of attack)
100.1CVE-2026-34909 EPSS over time2026-082026-11-01
VEDAS (exploit evidence)
100.9CVE-2026-34909 VEDAS over time2026-082026-11-01

Thin horizontal line: the “likely” (EPSS 0.10) or “strong” (VEDAS 0.90) threshold. Shaded “no data” areas are periods when cve-scores did not publish.

Who is affected

ProductAffectedNot affected
Ubiquiti Inc UniFi OS Serverbefore 5.0.8Not stated
Ubiquiti Inc Expressbefore 4.0.14Not stated
Ubiquiti Inc UDMbefore 5.1.12Not stated
Ubiquiti Inc UDM-Probefore 5.1.12Not stated
Ubiquiti Inc UDM-SEbefore 5.1.12Not stated
Ubiquiti Inc UDM-Pro-Maxbefore 5.1.12Not stated
Ubiquiti Inc UDM-Beastbefore 5.1.11Not stated
Ubiquiti Inc EFGbefore 5.1.12Not stated
Ubiquiti Inc UDWbefore 5.1.12Not stated
Ubiquiti Inc UDRbefore 5.1.12Not stated
Ubiquiti Inc UDR7before 5.1.12Not stated
Ubiquiti Inc UDR-5Gbefore 5.1.12Not stated
Ubiquiti Inc Express 7before 5.1.12Not stated
Ubiquiti Inc UNVRbefore 5.1.12Not stated
Ubiquiti Inc UNVR-Probefore 5.1.12Not stated
Ubiquiti Inc UNVR-Instantbefore 5.1.12Not stated
Ubiquiti Inc UNVR-G2before 5.1.12Not stated
Ubiquiti Inc UNVR-G2-Probefore 5.1.12Not stated
Ubiquiti Inc ENVRbefore 5.1.12Not stated
Ubiquiti Inc ENVR-Corebefore 5.1.12Not stated

12 more products are listed in the CVE record.

Version ranges exactly as the CVE record states them. “Before X” means X is the first fixed version.

Exploit Observer also maps it to: ubiquiti_networks unifi_os_server, ui unas_2_firmware, ui unas_4_firmware, ui unas_pro_4_firmware, ui unas_pro_8_firmware, ui unas_pro_firmware, ui unifi_express_7_firmware, ui unifi_express_firmware, ui unifi_os_server.

How to fix it

Fixed versions stated in the CVE record: 5.0.8, 4.0.14, 5.1.12, 5.1.11, 5.1.10.

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.

Vendor guidance:

How to detect it

There is no open VEDAS detection rule for this bug yet. It is listed on the detection gaps page if CISA has confirmed attacks.

References

Exploits and technical analysis

Government sources

Other references

Other databases

Where this comes from

This advisory is generated automatically by VEDAS from: CVE.org record, CISA KEV, cve-scores (EPSS and VEDAS), Exploit Observer. Text in quotes is reproduced from the source; everything else is a fixed template filled with source fields. Nothing here is written by a language model. Check the vendor advisory before acting, and read how VEDAS and Exploit Observer work, and their limits.