Symantec pcAnywhere Remote Code Execution

`=======  
Summary  
=======  
Name: Symantec pcAnywhere Remote Code Execution (Preauth)   
Release Date: 30 April 2012  
Reference: NGS00118  
Discoverer: Edward Torkington <[email protected]>  
Vendor: Symantec  
Vendor Reference:   
Systems Affected:   
  
Symantec pcAnywhere 12.5.x  
IT Management Suite 7.0 pcAnywhere Solution 12.5.x  
IT Management Suite 7.1 pcAnywhere Solution 12.6.x  
  
Risk: Critical  
Status: Published  
  
========  
TimeLine  
========  
Discovered: 14 September 2011  
Released: 26 September 2011  
Approved: 26 September 2011  
Reported: 26 September 2011  
Fixed: 24 January 2012  
Published: 30 April 2012  
  
===========  
Description  
===========  
Symantec pcAnywhere Version 12.5 and below is vulnerable to a remote code execution vulnerability. A flaw exists in the authentication component listening on TCP port 5631 which does not sufficiently validate user-submitted data.   
  
=================  
Technical Details  
=================  
  
It is possible to supply an invalid login that causes heap corruption and an object pointer overwrite. We end up in with a reliable overwrite of EAX as detailed below:  
  
mov ECX,DWORD PTR DS:[EAX]   
mov EDX,DWORD PTR DS:[ECX+8]  
push EAX  
call EDX  
  
A reliable overwrite in (non-rebasing/ASLR DLLs) of a fully patched Windows XP SP3 was found such that remote command execution can be gained.  
  
As the service restarts indefinitely, a reliable exploit in Windows 7 was also developed which effectively brute-forces a valid address to bypass ASLR.   
  
===============  
Fix Information  
===============  
http://www.symantec.com/security_response/securityupdates/detail.jsp?fid=security_advisory&pvid=security_advisory&year=2012&suid=20120124_00  
  
NGS Secure Research  
http://www.ngssecure.com  
`