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KDE's konqueror chooses low-security SSL ciphers by default
From: Ralf Hildebrandt <Ralf.Hildebrandt () charite de>
Date: Fri, 26 Nov 2004 23:48:50 +0100

Konqueror doesn't use the strongest cipher available if connecting using https. 

This was first spotted by Fridtjof Busse in
go there for the gory details.

E.g. konqueror uses 128bit RC4-MD5 even if 256bit AES is supported on both
sides.  Firefox on the same machine automagically uses the strongest cipher
(in this case AES-256). 

Problem: Instead of relying on the built-in autonegotation and
auto-selection that OpenSSL offers, a hardcoded list of ciphers is being
used. This list chooses low-strengh ciphers by default to be compatible with
broken servers.

This way, one cannot take neither take advantage of new ciphers (since
recompilation is required), nor of the strongest encryption possible.

Lutz Jänicke, OpenSSL developer says:

"I do not think that I understand this mess. I don't like code that bypasses
the given API (see the meth->get_cipher) access... man SSL_get_ciphers and
friends may help. 
I would rather recommend to simply leave the cipher selection to the
OpenSSL library (from time to time we do think about our default
settings)... "

Ralf Hildebrandt (i.A. des IT-Zentrum)          Ralf.Hildebrandt () charite de
Charite - Universitätsmedizin Berlin            Tel.  +49 (0)30-450 570-155
Gemeinsame Einrichtung von FU- und HU-Berlin    Fax.  +49 (0)30-450 570-962
IT-Zentrum Standort CBF                 send no mail to spamtrap () charite de

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