Posts tagged: Vulnerabilities

Jun 20 2012

Hackers Exploit Windows XML Core Services Vulnerability

An unpatched Windows vulnerability considered a critical threat by security experts is being exploited by cybercriminals.

Microsoft disclosed the flaw in XML Core Services (MSXML) 3.0, 4.0 and 6.0 June 12 during its monthly release of patches. The security advisory, which was separate from the patch release, offered a workaround for vulnerability CVE-2012-1889, but no fix.

Vulnerability CVE-2012-1889 is simple to exploit in all known versions of Internet Explorer. An attacker can make a CLSID-identification request by calling MSXML library methods and create an object identifier in order to try to access a non-existent object. Proof of Concept code for causing a crash looks like this:

msxml vulnerability

This code looks simple, but generates memory corruption and crashes Internet Explorer. The exploitation code tries to request a non-initialized object, but reference to memory region already exists. Memory corruption takes place in the helper function _dispatchImpl :: InvokeHelper() in the MSXML library.

Currently, this vulnerability has no patch available but Microsoft has released a Fix it solution. We strongly suggest that you consider this workaround – for now.

Jan 23 2012

Tor – Multiple Vulnerabilities

Tor LogoMultiple vulnerabilities have been found in Tor, the most severe of which may allow a remote attacker to execute arbitrary code.

Multiple vulnerabilities have been discovered in Tor:

  • When configured as client or bridge, Tor uses the same TLS certificate chain for all outgoing connections (CVE-2011-2768).
  • When configured as a bridge, Tor relays can distinguish incoming bridge connections from client connections (CVE-2011-2769).
  • An error in or/buffers.c could result in a heap-based buffer overflow (CVE-2011-2778).

Impact:
A remote attacker could possibly execute arbitrary code or cause a Denial of Service. Furthermore, a remote relay the user is directly connected to may be able to disclose anonymous information about that user or enumerate bridges in the user’s connection.

Vulnerable Versions:
< 0.2.2.35

Workaround:
There is no known workaround at this time.

Resolution:
All Tor users should upgrade to the latest version:

# emerge –sync
# emerge –ask –oneshot –verbose “>=net-misc/tor-0.2.2.35″

References:
CVE-2011-2768
CVE-2011-2769
CVE-2011-2778

Dec 22 2011

Kaspersky Internet Security – Memory Corruption Vulnerability

Kaspersky VulnerabilityVulnerability-Lab Team discovered a Memory & Pointer Corruption Vulnerability on Kaspersky Internet Security 2011/2012 & Kaspersky Anti-Virus 2011/2012.

Details:
The vulnerability is caused by an invalid pointer corruption when processing a corrupt .cfg file through the kaspersky exception filters, which could be exploited by attackers to crash the complete software process.
The bug is located over the basegui.ppl & basegui.dll when processing a .cfg file import.

Vulnerable Modules:
[+] CFG IMPORT

Affected Version(s):
– Kaspersky Anti-Virus 2012 & Kaspersky Internet Security 2012
– KIS 2012 v12.0.0.374
– KAV 2012 v12.x

– Kaspersky Anti-Virus 2011 & Kaspersky Internet Security 2011
– KIS 2011 v11.0.0.232 (a.b)
– KAV 11.0.0.400
– KIS 2011 v12.0.0.374

– Kaspersky Anti-Virus 2010 & Kaspersky Internet Security 2010

Severity:
Medium

Credits:
Vulnerability Research Laboratory – Benjamin K.M. (Rem0ve)

Original Advisory:
http://www.vulnerability-lab.com/get_content.php?id=129
http://www.vulnerability-lab.com/get_content.php?id=19

Dec 21 2011

Windows-7 Memory Corruption Vulnerability

Windows Memory CorruptionA vulnerability has been discovered in Microsoft Windows, which can be exploited by malicious people to potentially compromise a user’s system.

The vulnerability is caused due to an error in win32k.sys and can be exploited to corrupt memory via e.g. a specially crafted web page containing an IFRAME with an overly large “height” attribute viewed using the Apple Safari browser.

Successful exploitation may allow execution of arbitrary code with kernel-mode privileges.

The vulnerability is confirmed on a fully patched Windows 7 Professional 64-bit.
Other versions may also be affected.

Solution:
No effective solution is currently available.

Discovered By:
webDEViL

Original Advisory:
https://twitter.com/#!/w3bd3vil/status/148454992989261824

<iframe height=’18082563′></iframe> causes a BSoD on win 7 x64 via Safari. Lol!

Oct 27 2011

Facebook Attach EXE Vulnerability

Summary:
When using the Facebook ‘Messages’ tab, there is a feature to attach a file. Using this feature normally, the site won’t allow a user to attach an executable file. A bug was discovered to subvert this security mechanisms. Note, you do NOT have to be friends with the user to send them a message with an attachment.

Description:
When attaching an executable file, Facebook will return an error message stating:
“Error Uploading: You cannot attach files of that type.”

Facebook Error Uploading

When uploading a file attachment to Facebook we captured the web browsers POST request being sent to the web server. Inside this POST request reads the line:

Content-Disposition: form-data; name=”attachment”; filename=”cmd.exe”

It was discovered the variable ‘filename’ was being parsed to determine if the file type is allowed or not.

To subvert the security mechanisms to allow an .exe file type, we modified the POST request by appending a space to our filename variable like so:

filename=”cmd.exe ”

Facebook Post Hack

This was enough to trick the parser and allow our executable file to be attached and sent in a message.

Facebook Hot Stuff

Impact:
Potentially allow an attacker to compromise a victim’s computer system.

Affected Products:
www.facebook.com

Time Table:
09/30/2011 Reported Vulnerability to the Vendor
10/26/2011 Vendor Acknowledged Vulnerability
10/27/2011 Publicly Disclosed

Credits:
Discovered by Nathan Power
www.securitypentest.com

Execution POC: