Unifi AccessApplication · Ui

CVE-2025-52665

CRITICAL · 10.0 CVSS v3.1 Published 2025-10-31
Fix available
A fix is available. Upgrade to 4.0.21 or later.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A malicious actor with access to the management network could exploit a misconfiguration in UniFi’s door access application, UniFi Access, that exposed a management API without proper authentication. This vulnerability was introduced in Version 3.3.22 and was fixed in Version 4.0.21 and later.  Affected Products: UniFi Access Application (Version 3.3.22 through 3.4.31). 
 Mitigation: Update your UniFi Access Application to Version 4.0.21 or later.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

UniFi Access versions 3.3.22 through 3.4.31 contain a critical authentication bypass vulnerability where the management API is exposed without proper authentication due to a misconfiguration. An attacker with access to the management network can directly interface with this exposed API.

MitigationUpgrade UniFi Access Application to Version 4.0.21 or later to remediate the exposed management API misconfiguration.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Unifi AccessApplication
Affected:>= 3.3.22, < 4.0.21

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Changed
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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify UniFi Access installation
    Locate the UniFi Access application in your environment - check for the application running on your network or installed on your systems.
    Affected if UniFi Access software is present in the environment
  2. Determine installed UniFi Access version
    Check the version of the installed UniFi Access application - access the controller UI or use system commands to retrieve the software version.
    Affected if The installed version falls within 3.3.22 through 4.0.20 (inclusive)
  3. Verify management API accessibility
    Test if the UniFi Access management API endpoints are accessible from the network - attempt to reach the API port (commonly 8080 or 8443) from a system on the management network without providing credentials.
    Affected if The management API responds without requiring authentication
  4. Check network exposure of management interface
    Review firewall rules and network segmentation to determine if the UniFi Access management interface is exposed to the management network segment.
    Affected if The management API port is accessible from the management network without authentication restrictions

You are affected if UniFi Access version 3.3.22 through 4.0.20 is installed and the management API is accessible without authentication from your management network.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 4.0.21 or later
Fixed in 4.0.21
Interim mitigation

Upgrade UniFi Access Application to Version 4.0.21 or later to remediate the exposed management API misconfiguration.

Recommended fix High confidence

UniFi Access Application Version 4.0.21 or later

  1. Update your UniFi Access Application to Version 4.0.21 or later

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Unifi Access Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
7.0 hours of engineering $1,240
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,984.

Scan for this in your stack

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dbcve dependency scanner

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-52665 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data