Attacking the Vista Kernel

CNet reported not long ago about a new vulnerability found in the kernel of Vista[1]. The attack is a buffer overflow which corrupts the memory, and thus could be use for denial of service attacks. The report from Phion, the security company that reported the vulnerability, also states that the attack could be used to inject code[2].

There is a new vulnerability found in the kernel of Vista . The attack is a buffer overflow which corrupts the memory
There is a new vulnerability found in the kernel of Vista. The attack is a buffer overflow which corrupts the memory

The buffer overflow is caused by adding an IP address with an illegal subnet bits value to the IPv4 routing table: For example the following command will make Vista crash with a blue screen of death:

C:>route add 127.0.0.1/250 127.0.0.2

In the command above, we specified 254 as being the number of subnet bits, which is an illegal value. According to the vulnerability report by Thomas Unterleitner, the greater the value is, the quicker the crash is provoked[3].

The overflow is located into the CreateIpForwardEntry2 method which is part of the Iphlpapi library (Iphlpapi.dll). The problem arises because the method doesn’t verify the value of the PrefixLength property of DestinationPrefix specified in the MIB_IPFORWARD_ROW2 structure passed to the method. Therefore, the following code should crash the kernel[4]:

In order for this code to work you must be in the Administrators group or in the Network Operators Group…so it’s of limited use for most people, but you never know…

Microsoft said it had no intention of patching this buffer overflow before the next Vista service pack[5]. This exploit doesn’t apply to Windows XP.


[1] “Kernel vulnerability found in Vista”, David Meyer, CNet Security, November 22, 2008, http://news.cnet.com/8301-1009_3-10106173-83.html?part=rss&subj=news&tag=2547-1_3-0-20 (accessed on November 25, 2008)

[2] “Microsoft VISTA TCP/IP stack buffer overflow”, Thomas Unterleitner, November 19, 2008, http://www.securityfocus.com/archive/1/498471 (accessed on November 25, 2008)

[3] Ibid.

[4] Ibid. Code by Thomas Unterleitner

[5] “Vista kernel is vulnerable”, Egan Orion, The Inquirer, November 24, 2008, http://www.theinquirer.net/gb/inquirer/news/2008/11/24/vista-kernel-vulnerable (accessed on November 25, 2008)

Microsoft: Malware Up 38% in United States in 2008

According to the latest Security Intelligence Report from Microsoft, malicious software installations on computers increased 38% in the U.S for 2008.[1] Also, the number of “High Severity” vulnerabilities detected increased by 13% in the second half of 2007, putting the total of “High Severity” vulnerabilities to 48%.

Downloaders and droppers, accounting for 30% of all malicious software, with around 7 millions computers infected in the United States alone.

And of course, no good Microsoft document would be complete by stating that Vista in more awesome than XP, and therefore the report states that if you own Windows XP SP3, you’re likely to be infected 9 times on 1000 infections, while this number drops to 4 times on 1000 infections for Vista.

“For browser-based attacks on Windows XP-based machines, Microsoft vulnerabilities accounted for 42 percent of the total. On Windows Vista-based machines, however, the proportion of vulnerabilities attacked in Microsoft software was much smaller, accounting for just 6 percent of the total[2].”

Taken from the report:

Country/Region

2007

2008

% Chg.

Afghanistan

58.8

76.4

29.9

Bahrain

28.2

29.2

3.4

Morocco

31.3

27.8

-11.4

Albania

30.7

25.4

-17.4

Mongolia

29.9

24.7

-17.6

Brazil

13.2

23.9

81.8

Iraq

23.8

23.6

-1.1

Dominican Republic

24.5

23.2

-5.2

Egypt

24.3

22.5

-7.5

Saudi Arabia

22.2

22.3

0.4

Tunisia

15.9

21.9

37.3

Turkey

25.9

21.9

-15.4

Jordan

20.4

21.6

5.5

Former Yugoslav Republic of Macedonia

16.3

21.1

29.8

Lebanon

20.6

20.2

-1.8

Yemen

17.7

20.1

13.7

Portugal

14.9

19.6

31.7

Algeria

22.2

19.5

-12.2

Libya

17.3

19.5

13.1

Mexico

14.8

17.3

17

United Arab Emirates

18.2

17.3

-4.8

Monaco

13.7

17.0

23.7

Serbia

11.8

16.6

41.4

Bosnia and Herzegovina

12.8

16.3

27.5

Jamaica

15.0

16.3

8.9

Table 1.0 – Countries with the Highest Infection Rates[3]

See also:

“Microsoft Security Intelligence Report”, Microsoft, January-June 2008, http://www.microsoft.com/downloads/details.aspx?FamilyId=B2984562-47A2-48FF-890C-EDBEB8A0764C&displaylang=en (accessed on November 4, 2008)

“Les menaces en augmentation de 43%, dit Microsoft”, Marie-Ève Morasse, Cyberpresse, November 3, 2008, http://technaute.cyberpresse.ca/nouvelles/internet/200811/03/01-35773-les-menaces-en-augmentation-de-43-dit-microsoft.php (in French) (accessed on November 4, 2008)


[1] “Microsoft Security Intelligence Report”, Microsoft, January-June 2008, p. 122

[2] Ibid. p. 5

[3] Ibid. p.49