SecurityReason - uTorrent / BitTorrent Web UI HTTP "Range" Header DoS

Advisory Text :

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Secunia Research 11/06/2008

- uTorrent / BitTorrent Web UI HTTP "Range" Header DoS -

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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

* uTorrent 1.7.7 (build 8179)
* BitTorrent 6.0.1 (build 7859)

NOTE: Other versions may also be affected.

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2) Severity

Rating: Less critical
Impact: Denial of Service
Where: From remote

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3) Vendor's Description of Software

"uTorrent is a lightweight and efficient BitTorrent client for Windows
with many features.".

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

"BitTorrent is the global standard for accessing rich media over the
Internet."

http://www.bittorrent.com/

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4) Description of Vulnerability

Secunia Research has discovered a vulnerability in uTorrent and
BitTorrent, which can be exploited by malicious people to cause a DoS
(Denial of Service).

The vulnerability is caused due to an error in the handling of HTTP
requests and can be exploited to crash the application by sending an
HTTP request containing a malformed "Range" header string.

Successful exploitation requires that the Web UI interface is enabled
(not default).

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5) Solution

The vulnerability is fixed in BitTorrent version 6.0.3 (build 8642)
and in uTorrent version 1.8beta (build 10524).

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6) Time Table

31/01/2008 - Vendor notified.
04/02/2008 - Vendor notified (2nd attempt).
04/02/2008 - Vendor response.
27/05/2008 - Status update requested.
11/06/2008 - Public disclosure.

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7) Credits

Discovered by Dyon Balding, Secunia Research.

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8) References

The Common Vulnerabilities and Exposures (CVE) project has assigned
CVE-2008-0071 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/2008-7/

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

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