Re: [TLS] Broken browser behaviour with SCADA TLS

Peter Gutmann <> Thu, 05 July 2018 02:05 UTC

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From: Peter Gutmann <>
To: Kurt Roeckx <>, Hubert Kario <>
CC: "" <>
Thread-Topic: [TLS] Broken browser behaviour with SCADA TLS
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Date: Thu, 5 Jul 2018 02:05:48 +0000
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Subject: Re: [TLS] Broken browser behaviour with SCADA TLS
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Kurt Roeckx <> writes:

>The extensions are not related to TLS, but are extentions / add-ons of the
>browser itself. Firefox dropped support for the old way of doing extensions
>in version 57. They also added the WebExtensions API that is also implemented
>in other browsers. This required major rewrites of the extensions, and some
>were never changed to work with the new API.

As I understand it (E&OE), the flow was that a bunch of SCADA stuff used
browser extensions, presumably to talk things like IEC 61850.  When the
existing extensions broke, there was a general exodus from Firefox to Chrome,
however when Chrome broke at the TLS level there was indecision about what to
do.  There are also IE plugins, I assume the advice going forwards will be to
use IE.

(I have no idea about the prevalence of IE vs. others, but since it's the
default browser for Windows I assume this will be the easiest/recommended path
fowards, and until Windows 10 MS had a long history of being excruciatingly
careful about backwards compatibility so it seems the safest bet).