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Insomnia Security Vulnerability Advisory: ISVA-080623.1
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Name: Altiris Notification Server Agent - Privilege Escalation
Released: 23 June 2008
Advisory Update: 21 October 2008
Vendor Link:
http://www.altiris.com/
Affected Products:
Altiris Notification Server Agent 6.X
Original Advisory:
http://www.insomniasec.com/advisories/ISVA-080623.1.htm
Researcher:
Brett Moore, Insomnia Security
http://www.insomniasec.com
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Description
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Altiris Notification agent is installed as part of the
Altiris packages to allow the Notification Server to manage updates
for machines. It is usually installed to
C:\Program Files\Altiris\Altiris Agent and the main running agent
is called AeXNSAgent.exe.
By default the agent runs under the Local System account and is
vulnerable to numerous Shatter Attack vulnerabilities leading
to an attacker running code under the Local System privilege.
We reported a first instance of this vulnerabilty which was
then patched, we then alerted Symantec to the second vulnerabilty.
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Details
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The about window of the agent contains a Rich Text Box. This can
be viewed by clicking the About icon.
Exploitation of the RichTextBox takes the following steps;
* Locate the RichTextBox window
* Set the text to cmd
* Set the EditWordBreakProc of the RichTextBox to the location of
the system() API call
* Invoke the EditWordbreakProc function by double clicking the text.
The initial patch that was released made changes to the message
handler that prevents the messages used from reaching the window.
We then reported the second issue.
The notification agent has a listview as part of the visible Gui.
This listview can be used to overwrite memory within the
vulnerable process, leading to arbitrary command execution. This
has been heavily documented in various whitepapers and list posts.
By overwriting a function pointer, the unhandled exception pointer
or the PEB lock pointer, obtaining a system level shell is trivial.
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Solution
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Symantec have released a security update to address this issue;
http://www.symantec.com/avcenter/security/Content/2008.06.17.html
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Legals
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The information is provided for research and educational purposes
only. Insomnia Security accepts no liability in any form whatsoever
for any direct or indirect damages associated with the use of this
information.
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Insomnia Security Vulnerability Advisory: ISVA-080623.1
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