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Apple Mac OS X Security Framework Secure Transport may not negotiate the best cipher available

Vulnerability Note VU#734032

Original Release Date: 2006-11-30 | Last Revised: 2006-11-30


Apple Mac OS X Security Framework Secure Transport may not negotiate the best cipher available. This vulnerability may allow traffic to be weakly encrypted.


Secure Transport refers to Apple’s implementation of SSL and TLS that is used by Mac OS X to create secure connections over TCP/IP connections. According to Apple Security Update 2006-007:

Due to the order they are evaluated, it is possible for Secure Transport to use a cipher that provides no encryption or authentication when better ciphers are available. Applications using Secure Transport through CFNetwork, such as Safari, are not affected by this issue on systems with Security Update 2006-006 or later. This issue does not affect systems using Mac OS X v10.4.8 and later


A remote, unauthenticated attacker may be able to observe the plaintext of traffic believed to be securely encrypted.


Apply Apple Updates

This issue is addressed by Apple Security Update 2006-007.

Vendor Information


Apple Computer, Inc. Affected

Updated:  November 29, 2006



Vendor Statement

We have not received a statement from the vendor.

Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.


Refer to Apple Security Update 2006-007.

If you have feedback, comments, or additional information about this vulnerability, please send us email.

CVSS Metrics

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This issue was reported in Apple Security Update 2006-007. Apple credits Eric Cronin of gizmolabs for reporting this issue.

This document was written by Chris Taschner.

Other Information

CVE IDs: CVE-2006-4407
Severity Metric: 10.94
Date Public: 2006-11-28
Date First Published: 2006-11-30
Date Last Updated: 2006-11-30 15:20 UTC
Document Revision: 11

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