Ubiquiti UBB-XG/UDB-Pro/UDB-Pro-Sector/UBB airMAX Wireless Protocol command injection

CVSS Meta Temp Score
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CTI Interest Score
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8.6$0-$5k0.00

Summaryinfo

A vulnerability classified as critical was found in Ubiquiti UBB-XG, UDB-Pro, UDB-Pro-Sector and UBB. This affects an unknown part of the component airMAX Wireless Protocol. Executing a manipulation can lead to command injection. The identification of this vulnerability is CVE-2026-21638. The attack needs to be done within the local network. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Ubiquiti UBB-XG, UDB-Pro, UDB-Pro-Sector and UBB (version unknown). It has been declared as critical. This vulnerability affects an unknown function of the component airMAX Wireless Protocol. The manipulation with an unknown input leads to a command injection vulnerability. The CWE definition for the vulnerability is CWE-77. The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

A malicious actor in Wi-Fi range of the affected product could leverage a vulnerability in the airMAX Wireless Protocol to achieve a remote code execution (RCE) within the affected product. Affected Products: UBB-XG (Version 1.2.2 and earlier) UDB-Pro/UDB-Pro-Sector (Version 1.4.1 and earlier) UBB (Version 3.1.5 and earlier) Mitigation: Update your UBB-XG to Version 1.2.3 or later. Update your UDB-Pro/UDB-Pro-Sector to Version 1.4.2 or later. Update your UBB to Version 3.1.7 or later.

The advisory is shared for download at community.ui.com. This vulnerability was named CVE-2026-21638 since 01/01/2026. The exploitation appears to be easy. The attack needs to approached within the local network. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1202.

Upgrading eliminates this vulnerability. The upgrade is hosted for download at community.ui.com.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-0022). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Ubiquiti UniFi

Productinfo

Vendor

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.8
VulDB Meta Temp Score: 8.6

VulDB Base Score: 8.8
VulDB Temp Score: 8.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.8
CNA Vector (hackerone): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Command injection
CWE: CWE-77 / CWE-74 / CWE-707
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: community.ui.com

Timelineinfo

01/01/2026 CVE reserved
01/08/2026 +7 days Advisory disclosed
01/08/2026 +0 days VulDB entry created
01/09/2026 +1 days VulDB entry last update

Sourcesinfo

Advisory: community.ui.com
Status: Confirmed

CVE: CVE-2026-21638 (🔒)
GCVE (CVE): GCVE-0-2026-21638
GCVE (VulDB): GCVE-100-340144
CERT Bund: WID-SEC-2026-0022 - Ubiquiti UniFi Building Bridge und Device Bridge: Schwachstelle ermöglicht Codeausführung

Entryinfo

Created: 01/08/2026 19:00
Updated: 01/09/2026 09:04
Changes: 01/08/2026 19:00 (63), 01/09/2026 09:04 (7)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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