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On Fri, 25 Aug 2017 17:46:01 +0200 Hanno Böck wrote: |
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> On Wed, 23 Aug 2017 11:46:02 +0300 |
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> Andrew Savchenko <bircoph@g.o> wrote: |
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> |
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> > Sigh... https also makes MITM attacks possible, especially if SSL |
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> > or TLS < 1.2 is used or are allowed and protocol version downgrade |
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> > attack may be performed. |
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> |
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> None of that is true. |
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> |
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> You're probably referring to attacks that were specific to certain |
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> browser weaknesses, but they're irrelevant for this use case. |
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|
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Some attack are indeed implementation specific, but there are |
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several which are design flaws, e.g.: |
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|
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1) BEAST attack[1]: TLS 1.0 is vulnerable regrardless of |
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implementation (and all SSL versions). |
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|
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2) BREACH attack[2]: basically this is a side-channel attack for |
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compressed traffic. All TLS versions are still vulnerable, the only |
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practical mitigation is to disable compression. It can be argued if |
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this is a vulnerability in TLS or TLS protocol has nothing to do |
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with side channels, but if a protocol is vulnerable to a |
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side-channel implementation-agnostic attack, it is considered by |
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many as a protocol misdesign. |
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|
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Really SSL/TLS are very good examples of how crypto solutions should |
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not be designed and implemented. |
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|
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[1] https://www.gracefulsecurity.com/what-is-beast/ |
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[2] http://breachattack.com/ |
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|
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Best regards, |
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Andrew Savchenko |
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