LogonUI.exe

by Microsoft
Operating Systemmedium risk

Summary

Windows Logon UI (LogonUI.exe) renders the Windows logon screen, lock screen, and credential entry interface. It handles the visual presentation for user authentication, including password entry, smart card, Windows Hello, and other credential providers.

LogonUI.exe is the 128th most commonly executed Windows program in EchoTrail's dataset, observed 165,793 times across enterprise environments. It typically runs from C:\Windows\System32 and it is most often launched by winlogon.exe.

128th
most commonly executed Windows program
165,793
observed executions
medium
statistical confidence

Behavior

Top Paths

  • C:\Windows\System32100%

Top Hashes (SHA256)

  • 69ab1ba9247e34e0a6ddfdf3e737c48d70ffac2aca84491604ae53632d250d3728.88%
  • 8d6207ee0d1a0476fe26acdb725fdb2cea9b691afb6b578acd039da7aed9de4f21.36%
  • 536abc6d36a44a42c41263b0b470a5d2db75b9291585ae4efd94190c08c1c2339.57%
  • cf01e46c146699f6c0e3dd447043f59bc9438dbbcb9563af6c60ebc6d82727f28.85%
  • 630067181fa5b2e7d9e7f50c6cecf3c3e60eea426a7ab0125810e3337e14bae08.7%
  • 997c0e69c490770815dd64189ad2f59f8309ad266981bfc5d70a728dd174d19c6.09%
  • 9358ef8cb7fb08581d74274005263bd8fa2e6e0fc443930b25fd345cf6ce90715.6%
  • 09ab0535a54c2e2962f0fd06988d99060f8ceca39b07ac00a63204c773b958934.23%
  • aa62d29803d52ec06cd27ed3124e034048f09606eb7342181913c9817c7b44c52.62%
  • cabe8ff476f814df398735ad3ad993884ad100c9aa4c153b4bacb7ef9fb555f91.38%

Process Ancestry

Top Grandparents

Top Parents

Top Children

Rare or environment-specific process names are omitted from ancestry tables. Percentages are of all observed relationships.

Security Analysis

What does LogonUI.exe normally do?

Located in C:\Windows\System32. Almost always launched by winlogon.exe. Appears at boot, lock screen, and user switch events.

When is LogonUI.exe suspicious?

Parent process other than winlogon.exe. Running from a non-standard path. Spawning shells or unexpected child processes.

How do attackers abuse LogonUI.exe?

Accessibility feature abuse (Sticky Keys): attackers replace accessibility binaries (sethc.exe, utilman.exe, osk.exe) that are launched from the logon screen to get a SYSTEM-level shell without logging in. This appears in the process tree near logonui.exe. Name masquerading: malware may impersonate logonui.exe.

Detection guidance

Monitor for accessibility feature binaries being replaced or spawning shells at the logon screen. winlogon.exe spawning unusual children in addition to logonui.exe. logonui.exe running from non-standard paths.

False positive notes

Normal at boot, screen lock, and user switch events. Some OEM software (Toshiba indicators) may be launched alongside logonui.exe.

MITRE ATT&CK techniques

Related Processes

Ask Rocky about LogonUI.exe

Rocky answers questions about LogonUI.exe grounded in this same dataset — free, no account needed.

Need this data programmatically? The Rocky API includes 500 free lookups a month. Or just ask Rocky.

Data from EchoTrail's dataset of ~346M Windows process executions. Last extracted 2026-08-04.