NVD / CVE Program· CNA hackerone

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 u

Noroxi assessment

Priority: Now (action score 90/100)

CISA has confirmed exploitation in the wild (Jun 23, 2026). Remediation deadline for US federal agencies: Jun 26, 2026.
Probability of exploitation in the next 30 days: 68% (FIRST EPSS); higher than 99.3% of all records.
Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
According to CISA the attack is automatable: targets can be found by mass scanning.
Fixed version: Ubiquiti Inc EFG 5.1.12; Ubiquiti Inc ENVR 5.1.12; Ubiquiti Inc ENVR-Core 5.1.12.

Patch today or shut off access. Upgrade to Ubiquiti Inc EFG 5.1.12; Ubiquiti Inc ENVR 5.1.12; Ubiquiti Inc ENVR-Core 5.1.12 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · CISA KEV · FIRST EPSS

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.

CriticalCVSS 10.0 · v3.1KEVWeaponized Fix available

BDU:2026-07799

Published: May 21, 2026
Updated: Jul 23, 2026
EPSS: 68.0% · 99th percentile
CWE: CWE-22

Report tools

JSON

Action score

Now

Patch today or shut off access.

CVSS: 40 / 40 · 10.0 / 10
CISA KEV: 30 / 30 · Listed
EPSS: 20 / 30 · 68.0%

CISA SSVC decision

Exploitation: active
Automatable: yes
Technical impact: total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: —
CNA · hackerone: 10.0; NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Actively exploited in the wild

CISA added this to its Known Exploited Vulnerabilities catalog on Jun 23, 2026. That signals real attacks, not theory.

Remediation deadline for US federal agencies: Jun 26, 2026.

Get told when this record changes

In CISA KEV: exploitation in the wild confirmed
Weaponized exploit exists
A fix has been released

If any of these changes, we'll tell you in the daily email digest.

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
ui	unifi os server	cpe:2.3:a:ui:unifi_os_server
ui	unifi cloud gateway industrial firmware	cpe:2.3:o:ui:unifi_cloud_gateway_industrial_firmware
ui	unifi cloud gateway industrial	cpe:2.3:h:ui:unifi_cloud_gateway_industrial
ui	unifi dream machine firmware	cpe:2.3:o:ui:unifi_dream_machine_firmware
ui	unifi dream machine	cpe:2.3:h:ui:unifi_dream_machine
ui	unifi dream machine pro firmware	cpe:2.3:o:ui:unifi_dream_machine_pro_firmware
ui	unifi dream machine pro	cpe:2.3:h:ui:unifi_dream_machine_pro
ui	unifi dream machine special edition firmware	cpe:2.3:o:ui:unifi_dream_machine_special_edition_firmware
ui	unifi dream machine special edition	cpe:2.3:h:ui:unifi_dream_machine_special_edition
ui	unifi dream machine pro max firmware	cpe:2.3:o:ui:unifi_dream_machine_pro_max_firmware
ui	unifi dream machine pro max	cpe:2.3:h:ui:unifi_dream_machine_pro_max
ui	enterprise fortress gateway firmware	cpe:2.3:o:ui:enterprise_fortress_gateway_firmware

and 51 more

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

ui enterprise fortress gateway firmwarebefore 5.1.12
ui enterprise network video recorder core firmwarebefore 5.1.12
ui enterprise network video recorder firmwarebefore 5.1.12
ui unas 2 firmwarebefore 5.1.10
ui unas 4 firmwarebefore 5.1.10
ui unas pro 4 firmwarebefore 5.1.10
ui unas pro 8 firmwarebefore 5.1.10
ui unas pro firmwarebefore 5.1.10
ui unifi cloud gateway fiber firmwarebefore 5.1.12
ui unifi cloud gateway industrial firmwarebefore 5.1.12
ui unifi cloud gateway max firmwarebefore 5.1.12
ui unifi cloud gateway ultra firmwarebefore 5.1.12
ui unifi cloud key plus firmwarebefore 5.1.12
ui unifi cloudkey enterprise firmwarebefore 5.1.12
ui unifi cloudkey firmwarebefore 5.1.12
ui unifi dream machine beast firmwarebefore 5.1.11
ui unifi dream machine firmwarebefore 5.1.12
ui unifi dream machine pro firmwarebefore 5.1.12
ui unifi dream machine pro max firmwarebefore 5.1.12
ui unifi dream machine special edition firmwarebefore 5.1.12

Versions reported by the vendor

Affected version ranges reported by the assigning authority (hackerone). Independent of NVD's CPE analysis and usually ahead of it.

Ubiquiti Inc EFG
- before 5.1.12affected · semver
Ubiquiti Inc ENVR
- before 5.1.12affected · semver
Ubiquiti Inc ENVR-Core
- before 5.1.12affected · semver
Ubiquiti Inc Express
- before 4.0.14affected · semver
Ubiquiti Inc Express 7
- before 5.1.12affected · semver
Ubiquiti Inc UCG-Fiber
- before 5.1.12affected · semver
Ubiquiti Inc UCG-Industrial
- before 5.1.12affected · semver
Ubiquiti Inc UCG-Max
- before 5.1.12affected · semver
Ubiquiti Inc UCG-Ultra
- before 5.1.12affected · semver
Ubiquiti Inc UCK
- before 5.1.12affected · semver
Ubiquiti Inc UCK-Enterprise
- before 5.1.12affected · semver
Ubiquiti Inc UCKP
- before 5.1.12affected · semver

Same product

ui: all records

Other highest-scoring records for the same primary product.

CVE-2026-34910A malicious actor with access to the network could exploit an Improper Input Validation vulnerability found in UniFi OS devices to execute aKEV
97Now
CVE-2026-34908A malicious actor with access to the network could exploit an Improper Access Control vulnerability found in UniFi OS devices to make unauthKEV
96Now
CVE-2026-54402A malicious actor with access to the network and low privileges could exploit an Improper Input Validation vulnerability found in UniFi OS t
36Monitor

Published before and after this one in the same product

← EarlierCVE-2026-33000May 21, 2026 · A malicious actor with access to the network and high privileges could exploit an Improper Input Validation vulnerability found in UniFi OS
36Monitor
Later →CVE-2026-34911May 21, 2026 · A malicious actor with access to the network and low privileges could exploit a Path Traversal vulnerability found in UniFi OS devices to ac
30Monitor
Later →CVE-2026-54401Jul 2, 2026 · A malicious actor with access to the network and low privileges could exploit a Server-Side Request Forgery (SSRF) to escalate privileges wi
35Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
Ubiquiti Inc EFG	5.1.12	Vendor (CNA)
Ubiquiti Inc ENVR	5.1.12	Vendor (CNA)
Ubiquiti Inc ENVR-Core	5.1.12	Vendor (CNA)
Ubiquiti Inc Express	4.0.14	Vendor (CNA)
Ubiquiti Inc Express 7	5.1.12	Vendor (CNA)
Ubiquiti Inc UCG-Fiber	5.1.12	Vendor (CNA)
Ubiquiti Inc UCG-Industrial	5.1.12	Vendor (CNA)
Ubiquiti Inc UCG-Max	5.1.12	Vendor (CNA)
Ubiquiti Inc UCG-Ultra	5.1.12	Vendor (CNA)
Ubiquiti Inc UCK	5.1.12	Vendor (CNA)
Ubiquiti Inc UCK-Enterprise	5.1.12	Vendor (CNA)
Ubiquiti Inc UCKP	5.1.12	Vendor (CNA)
Ubiquiti Inc UDM	5.1.12	Vendor (CNA)
Ubiquiti Inc UDM-Beast	5.1.11	Vendor (CNA)
Ubiquiti Inc UDM-Pro	5.1.12	Vendor (CNA)
Ubiquiti Inc UDM-Pro-Max	5.1.12	Vendor (CNA)
Ubiquiti Inc UDM-SE	5.1.12	Vendor (CNA)
Ubiquiti Inc UDR	5.1.12	Vendor (CNA)
Ubiquiti Inc UDR-5G	5.1.12	Vendor (CNA)
Ubiquiti Inc UDR7	5.1.12	Vendor (CNA)
Ubiquiti Inc UDW	5.1.12	Vendor (CNA)
Ubiquiti Inc UNAS-2	5.1.10	Vendor (CNA)
Ubiquiti Inc UNAS-4	5.1.10	Vendor (CNA)
Ubiquiti Inc UNAS-Pro	5.1.10	Vendor (CNA)
Ubiquiti Inc UNAS-Pro-4	5.1.10	Vendor (CNA)
Ubiquiti Inc UNAS-Pro-8	5.1.10	Vendor (CNA)
Ubiquiti Inc UniFi OS Server	5.0.8	Vendor (CNA)
Ubiquiti Inc UNVR	5.1.12	Vendor (CNA)
Ubiquiti Inc UNVR-G2	5.1.12	Vendor (CNA)
Ubiquiti Inc UNVR-G2-Pro	5.1.12	Vendor (CNA)

Exploit status

Weaponized

A ready exploit tool or active in-the-wild use is known for this vulnerability. This should be your top priority.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

PublishedMay 21, 2026
CISA KEVJun 23, 2026+32 d
TodayNov 2, 2026+165 d

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

CVE-2026-5440342 days apartA malicious actor with access to the network could exploit a Path Traversal vulnerability found in certain devices running UniFi OS to bypas
34Monitor
CVE-2026-349110 days apartA malicious actor with access to the network and low privileges could exploit a Path Traversal vulnerability found in UniFi OS devices to ac
30Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

Anyone who can reach it over the internet can trigger it.
No account or password is required.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality: high · data can be read
Integrity: high · data or configuration can be modified
Availability: high · the service can be disrupted

Impact can extend beyond the vulnerable component (scope changes).

Attack vector: Network
Attack complexity: Low
Privileges required: None
User interaction: None
Scope: Changed
Confidentiality impact: High
Integrity impact: High
Availability impact: High

Weakness class (CWE)

CWE-22 · Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

nvd-secondary

Root cause

A user-supplied file name is joined with the allowed directory, but the result is never checked to confirm it is still inside that directory.

The bug in code

The whole CWE-22 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1const file = path.join(ROOT, req.query.name);
2res.sendFile(file);

Fixed

1const file = path.resolve(ROOT, req.query.name);
2if (!file.startsWith(ROOT + path.sep)) {
3  return res.sendStatus(400);
4}
5res.sendFile(file);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Attack patterns (CAPEC)

ATT&CK techniques

—

Change log

Fix✗ → ✓Sep 28, 2026, 10:09 PM UTC

For records you follow, these changes also arrive as notifications. →

References

community.ui.com/releases/Security-Advisory-Bulletin-064-064/84811c09-4cf4-42ab-bd61-cc994445963b

Show all references (1 more)

www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-34909

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records