Public Vulnerability Reports

Kaspersky Labs Anti-Virus IOCTL Local Privilege Escalation Vulnerability



Kaspersky Anti-Virus provides virus and spyware protection. More
information about Kaspersky Labs Anti-Virus can be found by visiting


Local exploitation of a design error vulnerability in Kaspersky Labs
Anti-Virus allows an attacker to execute arbitrary code with kernel

The vulnerability specifically exists due to improper address space
validation when the KLIN and KLICK device drivers processes IOCTL
0x80052110. By passing a specially crafted Irp structure to the affected
IOCTL handler, attackers can cause the driver to execute arbitrary code
via a CALL instruction using user supplied data. Execution of data
stored in user-land buffers is trivial.


Exploitation allows attackers to gain elevated privileges by executing
code within kernel context. This allows attackers to gain control of the
affected system. However, local access is required for exploitation to
be successful.


iDefense has confirmed the existence of this vulnerability within
version of the KLICK and KLIN device drivers as shipped with of Kaspersky Labs Anti-Virus. Previous versions are suspected
to be vulnerable as well.


iDefense is currently unaware of any effective workaround for this


Kaspersky Labs has addressed this vulnerability with version
of the KLIN.sys and KLICK.sys device drivers. These drivers can be
obtained by utilizing Kaspersky's Update update service.


The Common Vulnerabilities and Exposures (CVE) project has assigned the
name CVE-2006-4926 to this issue. This is a candidate for inclusion in
the CVE list (, which standardizes names for
security problems.


09/18/2006 Initial vendor notification
09/19/2006 Initial vendor response
10/19/2006 Coordinated public disclosure


This vulnerability was reported to iDefense by Rubén Santamarta of

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Copyright © 2006 Verisign, Inc.

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