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The U.S. Department of Energy
Computer Incident Advisory Capability
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INFORMATION BULLETIN
SkypeFind Vulnerability
[US-CERT Vulnerability Note VU#794236]
February 14, 2008 22:00 GMT Number S-185
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PROBLEM: The Skype client does not properly filter user-supplied input
that was received from the SkypeFind service. This
vulnerability may allow an attacker to execute arbitrary code.
PLATFORM: SkypeFind
DAMAGE: Execute arbitrary code.
SOLUTION: Skype has addressed this issue by filtering input supplied to
the SkypeFind service. Restrict access to the Skype URI
Blocking the skype: URI handler by using proxy servers or
application firewalls may prevent some remote vulnerabilities
in Skype from being exploited without user interaction.
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VULNERABILITY The risk is MEDIUM. The user-supplied script runs in the Local
ASSESSMENT: Machine Zone a remote unauthenticated attacker may be able to
exexute arbitrary code.
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LINKS:
CIAC BULLETIN: http://www.ciac.org/ciac/bulletins/s-185.shtml
ORIGINAL BULLETIN: http://www.kb.cert.org/vuls/id/794236
ADDITIONAL LINK: http://www.kb.cert.org/vuls/id/248184
CVE: http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=
CVE-2008-0583
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[***** Start US-CERT Vulnerability Note VU#794236 *****]
Vulnerability Note VU#794236
SkypeFind fails to properly sanitize user-supplied input
Overview
The Skype client does not properly filter user-supplied input that was received
from the SkypeFind service. This vulnerability may allow an attacker to execute
arbitrary code.
I. Description
Skype is a peer-to-peer application that provides Voice over IP (VoIP) and
Instant Messaging services. The Skype client is available for the Microsoft
Windows, Apple OS X and Linux operating systems. SkypeFind allows users to
review businesses. These reviews are viewable by others.
Skype does not properly filter input that was supplied to the SkypeFind full
name field. An attacker may be able to exploit this vulnerability by injecting
script into the full name field. When a user viewed the specially crafted
SkypeFind profile, the script would be run in the Internet Explorer Local
Machine Zone.
II. Impact
As explained in VU#248184, since the user-supplied script runs in the
Local Machine Zone a remote unauthenticated attacker may be able to
execute arbitrary code.
III. Solution
Skype has addressed this issue by filtering input supplied to the
SkypeFind service.
Restrict access to the Skype URI
Blocking the skype: URI handler by using proxy servers or application
firewalls may prevent some remote vulnerabilities in Skype from being
exploited without user interaction.
Systems Affected
Vendor Status Date Updated
Skype Technologies Vulnerable 6-Feb-2008
References
http://aviv.raffon.net/2008/01/31/AttackersCanSkypeFindYou.aspx
http://msdn2.microsoft.com/en-us/library/ms537183.aspx#local
http://www.skype.com/help/guides/skypefind.html
http://www.kb.cert.org/vuls/id/248184
Credit
This vulnerability was made public by Aviv Raff.
This document was written by Ryan Giobbi.
Other Information
Date Public 01/31/2008
Date First Published 02/13/2008 11:03:33 AM
Date Last Updated 02/13/2008
CERT Advisory
CVE Name CVE-2008-0582; CVE-2008-0583
US-CERT Technical Alerts
Metric 0.00
Document Revision 38
[***** End US-CERT Vulnerability Note VU#794236 *****]
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CIAC wishes to acknowledge the contributions of US-CERT for the
information contained in this bulletin.
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