PHP

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PHP in Linux calls a binary (sendmail) when the mail() function is executed. If we have putenv() allowed, we can set the environment variable "LD_PRELOAD", so we can preload an arbitrary shared object. Our shared object will execute our custom payload (a binary or a bash script) without the PHP restrictions, so we can have a reverse shell, for example.
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============================Exploit For Above Summary : 
Link : https://github.com/TarlogicSecurity/Chankro
>>> python2 chankro.py --arch 64 --input rev.sh --output chan.php --path /var/www/html