CVE-2019-25652: Ubiquiti UniFi Network Controller

High severity, CVSS 7.5. EPSS: 0.1% chance of exploitation in the next 30 days.

UniFi Network Controller before version 5.10.22 and 5.11.x before 5.11.18 contains an improper certificate verification vulnerability that allows adjacent network attackers to conduct man-in-the-middle attacks by presenting a false SSL certificate during SMTP connections. Attackers can intercept SMTP traffic and obtain credentials by exploiting the insecure SSL host verification mechanism in the SMTP certificate validation process.

Affected products

• Ubiquiti UniFi Network Controller: before 5.6.42 (fixed in 5.6.42); from 5.6.43, before 5.10.22 (fixed in 5.10.22); from 5.11, before 5.11.18 (fixed in 5.11.18)

Published 2026-03-27. Last modified 2026-06-17.