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I tested the latest Firefox beta using https://cc.dcsec.uni-hannover.de/ and all ciphers supported by Firefox 25 use MAC SHA1, none of them allow SHA-2. Can this be changed? Have Firefox plans to use SHA-2 in the future?

Beside, when I try to access a site that just support SHA-2 MACs, I got an error.


I tested on Ubuntu 13.10 using ppa:mozillateam/firefox-next to have Firefox using NSS 3.15.1 and result the same, no SHA256 ciphers was available. Chrome (with >= NSS 3.15.1) and Opera work fine.


I filed a bug to see if got some reply from Firefox developers, at support forum things are too quite.

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2 Answers 2

Cipher suites with HMACs using SHA-2 have been introduced in TLS 1.2. Currently, firefox only supports TLS 1.1. For more info on TLS 1.2 support, there is an open bug at mozilla's bugzilla (https://bugzilla.mozilla.org/show_bug.cgi?id=480514).

EDIT: As you noticed, the bug has been fixed at 25.0 beta. If you change the security.tls.version.max to 3 at the about:config page (it's in the link you provided) you can then visit https://www.ssllabs.com/ssltest/viewMyClient.html to test your client. At the bottom you will see that SHA-2 is supported.

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Thanks for your reply @Fotis That bug have an status of RESOLVED FIXED. Pls, note that I'm talking about Firefox 25 beta. –  gsc-frank Oct 4 '13 at 23:39
Another reference –  gsc-frank Oct 4 '13 at 23:58
Isn't better to ask this at firefox / mozilla dev forum? –  Darius Oct 5 '13 at 7:54
Ops, I'm really sorry, I was interested in this too and I was under the impression that there was still no support. I had the link in my bookmarks and just pasted it. –  Fotis Oct 5 '13 at 8:07
I create a request/question in the Firefox support forum. –  gsc-frank Oct 5 '13 at 12:43
up vote 0 down vote accepted

As noted here Firefox community is not pushing in this direction, seem to me that HMAC with SHA-2 will not be an option.

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