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.

Sigma rule (View on GitHub)

 1title: Self Extracting Package Creation Via Iexpress.EXE From Potentially Suspicious Location
 2id: b2b048b0-7857-4380-b0fb-d3f0ab820b71
 3status: experimental
 4description: |
 5    Detects the use of iexpress.exe to create binaries via Self Extraction Directive (SED) files located in potentially suspicious locations.
 6    This behavior has been observed in-the-wild by different threat actors.    
 7references:
 8    - https://strontic.github.io/xcyclopedia/library/iexpress.exe-D594B2A33EFAFD0EABF09E3FDC05FCEA.html
 9    - https://en.wikipedia.org/wiki/IExpress
10    - https://decoded.avast.io/janvojtesek/raspberry-robins-roshtyak-a-little-lesson-in-trickery/
11    - https://www.virustotal.com/gui/file/602f4ae507fa8de57ada079adff25a6c2a899bd25cd092d0af7e62cdb619c93c/behavior
12author: Joseliyo Sanchez, @Joseliyo_Jstnk, Nasreddine Bencherchali (Nextron Systems)
13date: 2024-02-05
14modified: 2024-06-04
15tags:
16    - attack.defense-evasion
17    - attack.t1218
18logsource:
19    category: process_creation
20    product: windows
21detection:
22    # VT Query: behavior_processes:"iexpress.exe" and behavior_processes:"/n /q /m" and behavior_processes:"*.sed*" and p:5+
23    selection_img:
24        - Image|endswith: '\iexpress.exe'
25        - OriginalFileName: 'IEXPRESS.exe'
26    selection_cli:
27        CommandLine|contains|windash: ' /n '
28    selection_paths:
29        CommandLine|contains:
30            # Note: Add more uncommon paths that fit your organizational needs.
31            - ':\ProgramData\'
32            - ':\Temp\'
33            - ':\Windows\System32\Tasks\'
34            - ':\Windows\Tasks\'
35            - ':\Windows\Temp\'
36            - '\AppData\Local\Temp\'
37    condition: all of selection_*
38falsepositives:
39    - Administrators building packages using iexpress.exe
40level: high

References

Related rules

to-top