1200KM / sigma-rule
Potentially Suspicious Self Extraction Directive File Created — Sigma Rule
Sigma rule ab90dab8-c7da-4010-9193-563528cfa347. Potentially Suspicious Self Extraction Directive File Created — Sigma Rule. Detects the creation of a binary file with the ".sed" extension. The ".sed" extension stand for Self Extraction Directive files. These files are used by the "iexpress.exe" utility in order to create self extracting packages. Attackers were seen abusing this utility and creating PE files with embedded ".sed" entries. Usually ".sed" files are simple ini files and not PE binaries.
Rule metadata and linked tags
Author: Joseliyo Sanchez, @Joseliyo_Jstnk. Source status: test; severity: medium. Source dates: 2024-02-05 / not supplied.
{
"product": "windows",
"category": "file_executable_detected"
}Pinned original Sigma rule · Detection Rule License 1.1
Source SHA-256: 6843fd34f32d0234886276fcfdcefe65b23710d8beadf813ae4e90f93fc366d1
Detection logic
Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.
title: Potentially Suspicious Self Extraction Directive File Created
id: ab90dab8-c7da-4010-9193-563528cfa347
related:
- id: 760e75d8-c3b5-409b-a9bf-6130b4c4603f
type: derived
status: test
description: |
Detects the creation of a binary file with the ".sed" extension. The ".sed" extension stand for Self Extraction Directive files.
These files are used by the "iexpress.exe" utility in order to create self extracting packages.
Attackers were seen abusing this utility and creating PE files with embedded ".sed" entries.
Usually ".sed" files are simple ini files and not PE binaries.
references:
- https://strontic.github.io/xcyclopedia/library/iexpress.exe-D594B2A33EFAFD0EABF09E3FDC05FCEA.html
- https://en.wikipedia.org/wiki/IExpress
- https://www.virustotal.com/gui/file/602f4ae507fa8de57ada079adff25a6c2a899bd25cd092d0af7e62cdb619c93c/behavior
author: Joseliyo Sanchez, @Joseliyo_Jstnk
date: 2024-02-05
tags:
- attack.stealth
- attack.t1218
logsource:
product: windows
category: file_executable_detected
detection:
selection:
TargetFilename|endswith: '.sed'
condition: selection
falsepositives:
- Unknown
level: medium
False positives
- Unknown
Source references
Connected ecosystem references
Exact source-tagged techniques
Telemetry review
Read the original logsource above, then inspect the linked detection workspaces for technique-level sensor context. No per-rule telemetry equivalence is inferred.
Pinned research references. No browser attack runner, live simulation result or validated detector is asserted. Source mappings and validation limits are preserved. ATT&CK / Atomic provenance · Detection provenance.