ZDI-11-021: Icon Labs Iconfidant SSL Server Key Length Remote Code Execution Vulnerability

http://www.zerodayinitiative.com/advisories/ZDI-11-021

January 20, 2011

-- CVSS:
10, (AV:N/AC:L/Au:N/C:C/I:C/A:C)

-- Affected Vendors:
Icon Labs

-- Affected Products:
Icon Labs Iconfidant SSL

-- TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability by Digital Vaccine protection filter ID 8034.
For further product information on the TippingPoint IPS, visit:

    http://www.tippingpoint.com

-- Vulnerability Details:
This vulnerability allows remote attackers to execute arbitrary code on
vulnerable installations of Icon Labs Iconfidant SSL Server.
Authentication is not required to exploit this vulnerability.

The specific flaw exists in the functionality responsible for key
exchange. If the sum of specific length fields within a client master
key packet exceeds 0x4000, a static buffer can be overflowed leading to
arbitrary code execution on the affected system.

-- Vendor Response:
Icon Labs states that this issue was first fixed in Iconfidant SSL 1.3.0
and recommends upgrading to Iconfidant 1.3.1.  Please contact Icon Labs
at support@icon-labs.com to update the latest Iconfidant SSL software.
"Icon Labs would like to thank an Anonymous researcher and
TippingPoint's Zero Day Initiative for responsibly reporting this
vulnerability, ZDI-CAN-403."

-- Disclosure Timeline:
2008-10-28 - Vulnerability reported to vendor
2011-01-20 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by:
    * Anonymous

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