[csw-users] Openssl vulnerability CVE-2009-3555

Yann Rouillard yann at pleiades.fr.eu.org
Sun Dec 6 13:04:20 CET 2009

Dear users,

A security vulnerability has been recently found in the TLS and SSL
protocol part related to the handling of session renegotiation [1]. This
vulnerability allows an attacker to inject arbitrary content at the
beginning of a TLS/SSL connection within a Man-in-the-middle attack.

This problem is caused by a design flaw in the TLS/SSL protocol and is
difficult to fix in a clean and backward compatible way. As a result the
new openssl release (0.9.8l) which fixes this bug simply completely
disables renegotiation.

This new package will hit csw unstable mirror very soon.

This modification should not have any impact for most setups except for
Apache https configurations which use certificate client verification
(SSLVerifyClient) or specify a new ssl cipher list (SSLCipherSuite) in a
directory or location context.
If that's your case, you should try to use these instructions on
the server or virtual host level, or avoid upgrading to openssl 0.9.8l 
[2], but you will stay vulnerable in the latter.

A new protocol extension to TLS is planned to address this issue but the
RFC draft is still under review and it will require both the client and
the server to implement the extension.

Best regards


[1] http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-3555
[2] You can avoid upgrading with pkgutil >= 1.9 by adding the following 
line in pkgutil.conf:

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