CVE-2019-5456

HIGHNVD 8.18.1—

8.1

SMTP MITM refers to a malicious actor setting up an SMTP proxy server between the UniFi Controller version <= 5.10.21 and their actual SMTP server to record their SMTP credentials for malicious use later.

CVSS v3: 8.1
EG Score: 8.1(medium)
EPSS: 57.9%
KEV: Not listed

Published

July 30, 2019

Last Modified

November 21, 2024

References (8)

support@hackeronehttps://community.ui.com/releases/862b962b-55f6-4324-96be-610f647d5c1c
support@hackeronehttps://community.ui.com/releases/9f698d0b-8279-40d3-9f1a-d36db4813124
support@hackeronehttps://community.ui.com/releases/Security-Advisory-Bulletin-003-003/982bbaa8-2a07-4f81-a5f6-0bb84753f391
support@hackeronehttps://hackerone.com/reports/519582
af854a3a-2127-422b-91ae-364da2661108https://community.ui.com/releases/862b962b-55f6-4324-96be-610f647d5c1c
af854a3a-2127-422b-91ae-364da2661108https://community.ui.com/releases/9f698d0b-8279-40d3-9f1a-d36db4813124
af854a3a-2127-422b-91ae-364da2661108https://community.ui.com/releases/Security-Advisory-Bulletin-003-003/982bbaa8-2a07-4f81-a5f6-0bb84753f391
af854a3a-2127-422b-91ae-364da2661108https://hackerone.com/reports/519582

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 9× in last 7d / 9× in last 30d)

Every time one of our enrichment pipelines (NVD, MITRE cvelistV5, EPSS, CISA KEV, GHSA, OSV, vendor advisories) ran against this CVE. Most recent first.

2026-05-27 13:39 UTCepss_batch
2026-05-27 13:38 UTCepss_batch
2026-05-26 13:42 UTCepss_batch
2026-05-26 07:17 UTCepss_batch
2026-05-26 07:17 UTCepss_batch
2026-05-26 07:17 UTCepss_batch
2026-05-24 16:47 UTCepss_batch
2026-05-23 03:06 UTCEG score recompute
2026-05-23 03:06 UTCGHSA enrichment

Frequently asked(5)

What is CVE-2019-5456?

CVE-2019-5456 is a high vulnerability published on July 30, 2019. SMTP MITM refers to a malicious actor setting up an SMTP proxy server between the UniFi Controller version <= 5.10.21 and their actual SMTP server to record their SMTP credentials for malicious use later.

When was CVE-2019-5456 disclosed?

CVE-2019-5456 was first published in the National Vulnerability Database on July 30, 2019, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2019-5456 actively exploited?

CVE-2019-5456 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 57.9% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2019-5456?

CVE-2019-5456 has a CVSS v3 base score of 8.1 (NVD).

How do I remediate CVE-2019-5456?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2019-5456, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2019-5456

Explore →

Is Your Infrastructure Affected by CVE-2019-5456?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs

CVE-2019-5456

📅 Published

🔄 Last Modified

🔗 References (8)