Secunia Research: BearShare NCTAudioFile2 ActiveX Control Buffer Overflow

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                 Secunia Research 09/05/2007

 - BearShare NCTAudioFile2 ActiveX Control Buffer Overflow -

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Table of Contents

Affected Software…1
Severity…2
Vendor's Description of Software…3
Description of Vulnerability…4
Solution…5
Time Table…6
Credits…7
References…8
About Secunia…9
Verification…10

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1) Affected Software

BearShare 6.0.2.26789

NOTE: Other versions may also be affected.

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2) Severity

Rating: Highly critical
Impact: System compromise
Where: Remote

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3) Vendor's Description of Software

"Share, Discover and Download music and videos."

Product Link:
http://www.bearshare.com/

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4) Description of Vulnerability

Secunia Research has discovered a vulnerability in BearShare, which
can be exploited by malicious people to compromise a user's system.

The vulnerability is caused due to a boundary error in the
NCTAudioFile2.AudioFile ActiveX control when handling the
"SetFormatLikeSample()" method. This can be exploited to cause a
stack-based buffer overflow by passing an overly long string (about
4124 bytes) as argument to the affected method.

Successful exploitation allows execution of arbitrary code when a user
e.g. visits a malicious website.

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5) Solution

Set the kill-bit for the affected ActiveX control.

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6) Time Table

30/04/2007 - Vendor notified.
09/05/2007 - Public disclosure.

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7) Credits

Discovered by Carsten Eiram, Secunia Research.

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8) References

The Common Vulnerabilities and Exposures (CVE) project has assigned
CVE-2007-0018 for the vulnerability.

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9) About Secunia

Secunia offers vulnerability management solutions to corporate
customers with verified and reliable vulnerability intelligence
relevant to their specific system configuration:

http://corporate.secunia.com/

Secunia also provides a publicly accessible and comprehensive advisory
database as a service to the security community and private
individuals, who are interested in or concerned about IT-security.

http://secunia.com/

Secunia believes that it is important to support the community and to
do active vulnerability research in order to aid improving the
security and reliability of software in general:

http://corporate.secunia.com/secunia_research/33/

Secunia regularly hires new skilled team members. Check the URL below
to see currently vacant positions:

http://secunia.com/secunia_vacancies/

Secunia offers a FREE mailing list called Secunia Security Advisories:

http://secunia.com/secunia_security_advisories/

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10) Verification

Please verify this advisory by visiting the Secunia website:
http://secunia.com/secunia_research/2007-50/

Complete list of vulnerability reports published by Secunia Research:
http://secunia.com/secunia_research/

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