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Self Extraction Directive File Created In Potentially Suspicious Location — Sigma Rule

Sigma rule 760e75d8-c3b5-409b-a9bf-6130b4c4603f. Self Extraction Directive File Created In Potentially Suspicious Location — Sigma Rule. Detects the creation of Self Extraction Directive files (.sed) in a potentially suspicious location. 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.

Rule metadata and linked tags

Author: Joseliyo Sanchez, @Joseliyo_Jstnk. Source status: test; severity: medium. Source dates: 2024-02-05 / not supplied.

Original logsource
{
  "category": "file_event",
  "product": "windows"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: d6cbefefe5108e190232e6e0900c204bb01e7d8f078a84afcdb2d7693488d06e

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.

Original Sigma rule YAML, scroll horizontally if needed
title: Self Extraction Directive File Created In Potentially Suspicious Location
id: 760e75d8-c3b5-409b-a9bf-6130b4c4603f
related:
    - id: ab90dab8-c7da-4010-9193-563528cfa347
      type: derived
status: test
description: |
    Detects the creation of Self Extraction Directive files (.sed) in a potentially suspicious location.
    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.
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:
    category: file_event
    product: windows
detection:
    selection:
        TargetFilename|contains:
            - ':\ProgramData\'
            - ':\Temp\'
            - ':\Windows\System32\Tasks\'
            - ':\Windows\Tasks\'
            - ':\Windows\Temp\'
            - '\AppData\Local\Temp\'
        TargetFilename|endswith: '.sed'
    condition: selection
falsepositives:
    - Unknown
level: medium

Original YAML and metadata in JSON

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 or production-validated detector is asserted. Imported procedures remain unvalidated; any bounded lab evidence has its own scope. ATT&CK / Atomic provenance · Detection provenance.