파일 확장자 검증 if문 수정 #208
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파일 확장자 검증 if문 수정 #208
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파일 확장자 우회 취약점 패치
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💡 개요
S3에 이미지 파일 업로드시 이중 확장자 공격을 통해 확장자 검증 조건문을 쉽게 우회할 수 있습니다.
S3Util.java
해당 if문은 이중 확장자 공격에 취약하기 때문에 if문의 조건을 수정하였습니다.
poc는 다음과 같습니다.
shellscript.png.sh📃 작업내용
>->!=로 변경