Re: Question for the Windows pros

[Nicolas RUFF <nicolas.ruff () gmail com>]

        Hello,

The ImpersonateNamedPipeClient() risks have been fully documented by
Blake Watts back in 2002.
http://www.blakewatts.com/namedpipepaper.html

The problem is basically that OpenFile() will accept either :
- A file path ("C:\toto.txt")
- A share path ("\\hacker\toto")
- A named pipe path ("\\hacker\pipe\toto")

(Did you ever notice that you cannot create a share named "pipe" on a
Windows system ? ;)

So if you can open a file with a privileged application (such as a
SYSTEM service), you can gain the privileges of the application.

Real life example: take your antivirus, change the log file name from
"C:\Program Files\Antivirus\log.txt" to "\\mycomputer\pipe\toto" while
running a listener on the "toto" pipe. When the antivirus opens the log
file, you become SYSTEM.

Regards,
- Nicolas RUFF
Security Researcher @ EADS-CRC
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