The Journal of the Convergence on Culture Technology (문화기술의 융합)

The International Promotion Agency of Culture Technology (국제문화기술진흥원)
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A Study on Forgery Techniques of Smartphone Voice Recording File Structure and Metadata

스마트폰 음성녹음 파일 구조 및 메타데이터의 위변조 기법에 관한 연구

  • 박재완 (숭실대학교 글로벌미디어학부) ;
  • 곽원준 (숭실대학교 경영학부, 가톨릭대학교 인공지능학과) ;
  • 이상현 (숭실대학교 국제법무학과)
  • Received : 2022.09.30
  • Accepted : 2022.11.01
  • Published : 2022.11.30
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Abstract

Recently, as the number of voice recording files submitted as court evidence increases, the number of cases claiming forgery is also increasing. If the audio recording file structure and metadata, which are objective grounds, are completely forged, it is actually impossible to detect forgery of the sophisticated audio recording file. It is extremely rare for the court to reject the file structure and metadata analysis performed with the forged audio recording file. The purpose of this study is to prove that forgery of voice recording file structure and metadata is easily possible. To this end, in this study, it was introduced that forgery detection is impossible when the 'mixed paste' function, which enables sophisticated editing based on the typification of the editing method of voice recording files, is applied. Moreover, it has been proven through experiments that forgery of file structure and metadata is possible. Therefore, a stricter standard for judging the admissibility of evidence is required when the audio recording file is adopted as digital evidence. This study will not only contribute to the standard of integrity in the adoption of digital evidence by judges, but will also contribute to the method of constructing a dataset for artificial intelligence in detecting forgery of recorded files that is expected to be developed in the future.

최근 음성녹음 파일도 법정 증거로 제출되는 수가 늘어남에 따라 위변조를 주장하는 사례도 증가하고 있다. 객관적 근거인 음성녹음 파일 구조 및 메타데이터를 완벽하게 위변조 할 경우에는 정교한 음성녹음 파일의 위변조 검출은 사실상 불가능하다. 위변조된 음성녹음 파일을 가지고 수행된 파일 구조 및 메타데이터 분석이 법정에서 거부되는 것은 쉽지 않다. 본 연구는 음성녹음 파일 구조 및 메타데이터의 위변조가 손쉽게 가능하다는 것을 증명하는 것을 목적으로 한다. 이를 위해 본 연구에서는 음성녹음 파일의 편집 방법의 유형화를 기반으로 정교한 편집이 가능한 '혼합붙여넣기' 기능을 적용할 경우 위변조 검출의 불가능함을 소개했다. 더욱이 실험을 통해 파일 구조 및 메타데이터의 위변조가 가능하다는 것을 증명했다. 따라서 음성녹음 파일이 디지털 증거로 채택됨에 있어서 더 엄격한 증거능력 판단 기준이 필요하다. 본 연구는 법관이 디지털 증거를 채택함에 무결성의 기준에 공헌할 뿐만 아니라 향후 개발될 것으로 예상되는 녹음파일 위변조 검출 인공지능을 위한 데이터셋 구축 방법에 공헌할 것이다.

Keywords

Acknowledgement

이 연구는 2020년도 숭실대학교 교내연구비 지원(융합연구)에 의한 연구임

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