webProeasy

Grep It All

web-kids20

A "full shell" service at https://2019-10-13-cmdinj.ctf.su/task/grep, but you can only get digits. The service runs user commands but pipes output through `grep -Eo "[0-9]+"` to only show numbers. Flag is in /flag.

$ ls tags/ techniques/
command_injectionshellwaf_bypassshgrepcomment
shell_comment_injectionoutput_filter_bypass
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