Improper Certificate Verification in UniFi Network Controller by Ubiquiti
CVE-2019-25652

7.7HIGH

Key Information:

Vendor

Ubiquiti

Status
Unifi Network Controller
Vendor
CVE Published:
27 March 2026

What is CVE-2019-25652?

The UniFi Network Controller has a vulnerability that allows adjacent network attackers to perform man-in-the-middle attacks. By exploiting an insecure SSL host verification mechanism in the SMTP certificate validation process, attackers can present a fraudulent SSL certificate. This allows them to intercept SMTP traffic and potentially capture user credentials, posing significant security risks to affected environments.

Affected Version(s)

UniFi Network Controller 0 < 5.6.42

UniFi Network Controller 5.6.43 < 5.10.22

UniFi Network Controller 5.11 < 5.11.18

References

https://community.ui.com/releases/Security-Advisory-Bulle...
vendor-advisory
https://www.vulncheck.com/advisories/unifi-network-contro...
third-party-advisory

CVSS V4

Score:
7.7
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Adjacent Network
Attack Complexity:
High
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.