MS11-013: Vulnerabilities in Kerberos Could Allow Elevation of Privilege (2496930)

This script is Copyright (C) 2011-2014 Tenable Network Security, Inc.


Synopsis :

The remote implementation of Kerberos is affected by one or more
vulnerabilities.

Description :

The implementation of Kerberos on the remote Windows host is affected
by one or more vulnerabilities :

- Microsoft's Kerberos implementation uses a weak hashing
mechanism, which can allow for certain aspects of a
Kerberos service ticket to be forged. Note that this is
not exploitable on domains where the domain controllers
are running Windows Server 2008 or Windows Server 2008
R2. (CVE-2011-0043)

- An attacker can force a downgrade in Kerberos
communication between a client and server to a weaker
encryption standard than negotiated originally by means
of a man-in-the-middle attack because Windows does not
correctly enforce the stronger default encryption
standards included in Windows 7 and Windows Server 2008
R2. Note that this issue only affects implementations
of Kerberos on Windows 7 and Windows Server 2008 R2.
(CVE-2011-0091)

See also :

http://technet.microsoft.com/en-us/security/bulletin/ms11-013

Solution :

Microsoft has released a set of patches for Windows XP, 2003, 7, and
2008 R2.

Risk factor :

High / CVSS Base Score : 7.2
(CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C)
CVSS Temporal Score : 5.3
(CVSS2#E:U/RL:OF/RC:C)
Public Exploit Available : false

Family: Windows : Microsoft Bulletins

Nessus Plugin ID: 51913 ()

Bugtraq ID: 46130
46140

CVE ID: CVE-2011-0043
CVE-2011-0091