Encrypted Pastebin - FLAG0

0x00 Home

0x01 Try Post

http://127.0.0.1/xxxxxxxxxx/?post=6ybKGEfF47eN1k5eyj!lsraaVXFME-xBz51ocCeiAZPULUMIemubmPanqBO04ixb-01L-Qek7nUeXitmNAEMNrJ5BbfeP5GWD1hYEuHciAk81fRa4IyuvmcIG3sE1K11mM7s7hA1P1mChArqJR4i5wSrOF7O561nOHu!lGQcA1iFos-jU6x7iy-TJ4iI4yZjnHkcdXT2F9y6fH4!TY!DcA~~

The result page can decode the post param back to the title and body

0x02 Modify the Param

Added 12345 as prefix for param post

http://127.0.0.1/xxxxxxxxxx/?post=123456ybKGEfF47eN1k5eyj!lsraaVXFME-xBz51ocCeiAZPULUMIemubmPanqBO04ixb-01L-Qek7nUeXitmNAEMNrJ5BbfeP5GWD1hYEuHciAk81fRa4IyuvmcIG3sE1K11mM7s7hA1P1mChArqJR4i5wSrOF7O561nOHu!lGQcA1iFos-jU6x7iy-TJ4iI4yZjnHkcdXT2F9y6fH4!TY!DcA~~

Caused errors and get a flag.