The uploaded files can only be harmless files, including but not limited to: jpg, png, bmp, txt, zip, rar, mp3, etc. The white list is used to limit the type of uploaded files, and the file type is determined by detecting the file content. The type of files can be judged by detecting the contents of files, and the upload of executable script files and executable programs can be restricted, including but not limited to: asp, aspx, php, jsp, exe, etc. The technical threshold of some file upload vulnerabilities is very low, which is easy for attackers to implement.īecause webshell mostly appears in the form of dynamic script, some people call it the back door tool of website. The files uploaded here can be Trojans, viruses, malicious scripts or WebShell. The ascii() function is to convert characters into ASCII codes, and finally confirm what the first character is according to the prompts step by step, change the substr parameters, judge other characters, and finally confirm the database name.īenchmark(count,expr) As a result of this function, the expression expr implement count Times.
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. Archives
August 2023
Categories |