Security readout for executives and security teams
Plain-English summary
UniFi Controller versions 5.10.21 and earlier may expose SMTP credentials if an attacker can position a malicious SMTP proxy between the controller and the real mail server. The business risk is unauthorized reuse of those mail credentials, not direct takeover of the controller based on the provided sources.
Executive priority
Treat this as a targeted credential-protection issue. Prioritize if UniFi Controller manages production networks and uses shared or privileged SMTP credentials. Urgency increases where network interception risk exists.
Technical view
CVE-2019-5456 is described as SMTP man-in-the-middle exposure in UniFi Controller <= 5.10.21, mapped to CWE-300. The public bundle does not include CVSS scoring, detailed patch notes, or proof of active exploitation. The known impact is capture of configured SMTP credentials during mail-server communication.
Likely exposure
Exposure is likely limited to organizations running UniFi Controller 5.10.21 or earlier with SMTP configured and an attacker able to intercept or proxy SMTP traffic.
Exploitation context
The CVE is not listed as KEV in the provided bundle, and no cited source states active exploitation. Abuse requires network positioning between the controller and SMTP server, then credential misuse after capture.
Researcher notes
The evidence identifies affected versions and credential-capture impact, but not a CVSS score, exploit-in-the-wild confirmation, or exact fixed release in the bundle. Avoid assuming broader UniFi product impact beyond the listed UniFi Controller scope.
Mitigation direction
- Identify UniFi Controller deployments and confirm installed versions.
- Review Ubiquiti advisory and release notes for the vendor-supported fixed version.
- Upgrade affected controllers according to vendor guidance.
- If interception is suspected, rotate SMTP credentials after securing the mail path.
- Prefer protected SMTP transport where supported by vendor and mail provider.
Validation and detection
- Check whether any UniFi Controller is version 5.10.21 or earlier.
- Confirm whether SMTP settings are configured on affected controllers.
- Review mail-server logs for unusual authentication sources or timing.
- Verify controller-to-SMTP routing does not traverse untrusted proxy paths.
- Document vendor advisory status and remediation evidence.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-300: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2019-5456 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://hackerone.com/reports/519582CVE reference · x_refsource_MISC
- https://community.ui.com/releases/Security-Advisory-Bulletin-003-003/982bbaa8-2a07-4f81-a5f6-0bb84753f391CVE reference · x_refsource_CONFIRM
- https://community.ui.com/releases/862b962b-55f6-4324-96be-610f647d5c1cCVE reference · x_refsource_CONFIRM
- https://community.ui.com/releases/9f698d0b-8279-40d3-9f1a-d36db4813124CVE reference · x_refsource_CONFIRM
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Channel Accessible by Non-Endpoint
Channel Accessible by Non-Endpoint represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.