Summary of MySQL injection bypass filtering techniques, mysql injection bypass Filtering

Summary of MySQL injection bypass filtering techniques, mysql injection bypass Filtering

First, let's look at the GIF operation:

Case 1: space is filtered

Use parentheses () instead of spaces. Any statement that can calculate the result can be surrounded by parentheses;

select * from(users)where id=1;

Use comments/**/to bypass spaces;

select * from/**/users/**/where id=1;

Case 2: restrict the combination of from and certain characters

Add a vertex after from. That is, use from. To replace from;

select * from. users where id=1;

Then you can directly view the GIF:

To put it bluntly, you just need'Field name'ReplaceHex;

This will be associated with the use of SQL Injectionload_fileOrinto outfileFrequently Used hex to encode a sentence and then import it;

Here, we do not need to use single or double quotation marks (magic_quotes_gpc()I will not mention it );

But at that time, I only looked at the results. Today I found this problem when I sorted out the previous materials, but I was dizzy and did not know why it was so encoded. The actual operation is as follows:

You can clearly see the error,selectThe first 'single quote 'behind it, and in a Trojan horsecmdThe previous single quotes are closed, leading to an error in the subsequent statements;

Then converthex, Remove the quotation marks and find that the data can be written;

Here, my host does not give him the permission and will prompt that he cannot write it. I still need to check the situation;

Summary

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