Ubiquiti fixes 2 vulnerabilities

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[TLP:CLEAR] Ubiquiti fixes 2 vulnerabilities

Ubiquiti fixes 2 vulnerabilities in its products [1][2]. Products and their fixed versions: airMAX AC - 8.7.21 [1] airMAX M - 6.3.24 [1] airFiber AF60-XG - 1.2.3 [1] airFiber AF60 - 2.6.8 [1] UBB-XG - 1.2.3 [2] UDB-Pro/UDB-Pro-Sector - 1.4.2 [2] UBB - 3.1.7 [2]

airMAX, airFiber, UBB, UDB - RCE (CVE-2026-21639, CVE-2026-21638)

CVSS 8.8 (High)

An unauthenticated attacker within Wi-Fi range of the affected product can exploit a vulnerability in the airMAX Wireless Protocol and achieve remote code execution [1][2].

The vulnerability is present in products:

airMAX AC; <=8.7.20
airMAX M; <=6.3.22
airFiber AF60-XG; <=1.2.2
airFiber AF60; <=2.6.7
UBB-XG; <=1.2.2
UDB-Pro/UDB-Pro-Sector; <=1.4.1
UBB; <=3.1.5

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

More information:

CVE-2026-21639 at cve.org, NVD
CVE-2026-21638 at cve.org, NVD
CWE-77: Improper Neutralization of Special Elements used in a Command ('Command Injection') at cwe.mitre.org

The vulnerability was publicly disclosed 6. 1. 2026.

Links

By CESNET, z.s.p.o. Michaela Jarošová on 9. 1. 2026.

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[TLP:CLEAR] Ubiquiti fixes 2 vulnerabilities

airMAX, airFiber, UBB, UDB - RCE (CVE-2026-21639, CVE-2026-21638)

CVSS 8.8 (High)

Links