sigmahighHunting

Self Extracting Package Creation Via Iexpress.EXE From Potentially Suspicious Location

Detects the use of iexpress.exe to create binaries via Self Extraction Directive (SED) files located in potentially suspicious locations. This behavior has been observed in-the-wild by different threat actors.

MITRE ATT&CK

T1218

defense-evasion

Detection Query

selection_img:
  - Image|endswith: \iexpress.exe
  - OriginalFileName: IEXPRESS.exe
selection_cli:
  CommandLine|contains|windash: " /n "
selection_paths:
  CommandLine|contains:
    - :\ProgramData\
    - :\Temp\
    - :\Windows\System32\Tasks\
    - :\Windows\Tasks\
    - :\Windows\Temp\
    - \AppData\Local\Temp\
condition: all of selection_*

Author

Joseliyo Sanchez, @Joseliyo_Jstnk, Nasreddine Bencherchali (Nextron Systems)

Created

2024-02-05

Data Sources

windowsProcess Creation Events

Platforms

windows

References

Tags

attack.defense-evasionattack.t1218

Raw Content

title: Self Extracting Package Creation Via Iexpress.EXE From Potentially Suspicious Location
id: b2b048b0-7857-4380-b0fb-d3f0ab820b71
status: test
description: |
    Detects the use of iexpress.exe to create binaries via Self Extraction Directive (SED) files located in potentially suspicious locations.
    This behavior has been observed in-the-wild by different threat actors.
references:
    - https://strontic.github.io/xcyclopedia/library/iexpress.exe-D594B2A33EFAFD0EABF09E3FDC05FCEA.html
    - https://en.wikipedia.org/wiki/IExpress
    - https://decoded.avast.io/janvojtesek/raspberry-robins-roshtyak-a-little-lesson-in-trickery/
    - https://www.virustotal.com/gui/file/602f4ae507fa8de57ada079adff25a6c2a899bd25cd092d0af7e62cdb619c93c/behavior
author: Joseliyo Sanchez, @Joseliyo_Jstnk, Nasreddine Bencherchali (Nextron Systems)
date: 2024-02-05
modified: 2024-06-04
tags:
    - attack.defense-evasion
    - attack.t1218
logsource:
    category: process_creation
    product: windows
detection:
    # VT Query: behavior_processes:"iexpress.exe" and behavior_processes:"/n /q /m" and behavior_processes:"*.sed*" and p:5+
    selection_img:
        - Image|endswith: '\iexpress.exe'
        - OriginalFileName: 'IEXPRESS.exe'
    selection_cli:
        CommandLine|contains|windash: ' /n '
    selection_paths:
        CommandLine|contains:
            # Note: Add more uncommon paths that fit your organizational needs.
            - ':\ProgramData\'
            - ':\Temp\'
            - ':\Windows\System32\Tasks\'
            - ':\Windows\Tasks\'
            - ':\Windows\Temp\'
            - '\AppData\Local\Temp\'
    condition: all of selection_*
falsepositives:
    - Administrators building packages using iexpress.exe
level: high