perl, 115 bytes

Result

AC

Duration

802ms

Code [DL]

print$a=$b=<>;$a=~tr/T/*/;<>;$c=$_,print$a for<>;$_=$a^$b^$c;s/\^ *(?=K)|(?<=K) *\^/'*'x length($&)/e;tr/5/K/;print

stdin

                T                                 
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
       K                                          

stdout

                T                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
                *                                 
       K*********                                 

stderr

strace

10    execve("/bin/sh", ["/bin/sh", "/root/script", "/volume/CODE"], 0x7ffd3fd368c0 /* 7 vars */) = 0
11    execve("/bin/cat", ["cat", "-"], 0x5584cfa38d30 /* 7 vars */) = 0
12    execve("/usr/bin/perl", ["/usr/bin/perl", "/volume/CODE"], 0x5584cfa38d40 /* 7 vars */) = 0
11    +++ exited with 0 +++
10    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=11, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
12    +++ exited with 0 +++
10    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=12, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
10    +++ exited with 0 +++