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@@ -198,22 +198,29 @@ difficult to write good, reliable software parsing a X.509 certificate.
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The first, important difference to point out here is that SSLv2 is no more
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The first, important difference to point out here is that SSLv2 is no more
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considered secure. There are known attacks on the ciphers adopted (md5, for
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considered secure. There are known attacks on the ciphers adopted (md5, for
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-example) as well as protocol flaws.
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+example \cite{rfc6176}) as well as protocol flaws.
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SSLv2 would allow a connection to be closed via a not-authenticated TCP segment
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SSLv2 would allow a connection to be closed via a not-authenticated TCP segment
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-with the \texttt{FIN} flag set. Padding informations are sent in clear, and the
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-payload is not compressed before encrypting, allowing a malicious attacker
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-traffic analysis capabilities. The ciphersuite is negotiated using
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+with the \texttt{FIN} flag set (\cite{rfc6176} \S 2). Padding informations are sent in
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+clear, and the payload is not compressed before encrypting, allowing a malicious
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+attacker traffic analysis capabilities \cite{sslpadding}. The ciphersuite is negotiated using
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non-authenticated informations, allowing an attacker to influence the choice of
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non-authenticated informations, allowing an attacker to influence the choice of
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-the \texttt{Cipher Spec} and weaken the security of the communication.
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+the \texttt{Cipher Spec} and weaken the security of the communication
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+\cite{rfc6176} \S 2.
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Most of these vulnerabilities have been addressed by the later SSLv3, which
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Most of these vulnerabilities have been addressed by the later SSLv3, which
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introduced compression and protection against truncation attacks.
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introduced compression and protection against truncation attacks.
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Its standardized twin, TLS 1.0, only differs on the cipher suite and key
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Its standardized twin, TLS 1.0, only differs on the cipher suite and key
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calculation requirements, strengthen in order to increase the security of the
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calculation requirements, strengthen in order to increase the security of the
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-channel.
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+channel \cite{rfc2246}.
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Both SSLv3 and TLS 1.0 have been threatened in 2011 by an attack that could break
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Both SSLv3 and TLS 1.0 have been threatened in 2011 by an attack that could break
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the same origin policy, known as BEAST. It is not dramatic, and almost any
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the same origin policy, known as BEAST. It is not dramatic, and almost any
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browser now mitigates its spectrum of action.
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browser now mitigates its spectrum of action.
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-TLS 1.1, and TLS 1.2 are considered safe as of today.
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+
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+Even if TLS 1.1, and TLS 1.2 are considered safe as of today, attacks such as
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+CRIME, and lately BREACH constitute a new and valid instance of threat for HTTP
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+compressions mechanisms. However, as their premises go beyond the scope of this
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+document, those attacks have not been analyzed. For forther informations, see
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+\url{http://breachattack.com/}.
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+
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%%% Local Variables:
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%%% Local Variables:
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%%% mode: latex
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%%% mode: latex
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%%% TeX-master: "question_authority.tex"
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%%% TeX-master: "question_authority.tex"
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