Weak ciphers configured in haproxy reported by ssllabs

[Daniel-at-git]

Hello,

a normal (3.0-)BBB-installation results on grade A on ssllabs with weak ciphers activated. Those weak ciphers are not used by any (popular) client and those clients are not supported:
IE 11 / Win Phone 8.1
Safari 6 / iOS 6.0.1
Safari 7 / iOS 7.1
Safari 7 / OS X 10.9
Safari 8 / iOS 8.4
Safari 8 / OS X 10.10

With
https://ssl-config.mozilla.org/#server=haproxy&version=2.4.24&config=intermediate&openssl=3.4.2&guideline=5.7
you get the following configuration
ssl-default-bind-curves X25519:prime256v1:secp384r1
ssl-default-bind-ciphers ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:DHE-RSA-CHACHA20-POLY1305
ssl-default-bind-ciphersuites TLS_AES_128_GCM_SHA256:TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256
ssl-default-bind-options prefer-client-ciphers ssl-min-ver TLSv1.2 no-tls-tickets
ssl-default-server-ciphers ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:DHE-RSA-CHACHA20-POLY1305
ssl-default-server-ciphersuites TLS_AES_128_GCM_SHA256:TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256
ssl-default-server-options ssl-min-ver TLSv1.2 no-tls-tickets

haproxy.cfg is overwritten by bbb-install in
https://github.com/bigbluebutton/bbb-install/blob/v3.0.x-release/bbb-install.sh#L744

A (git) diff to fix this issue could like this

diff --git a/bbb-install.sh b/bbb-install.sh
index a079fa9..223a3c2 100644
--- a/bbb-install.sh
+++ b/bbb-install.sh
@@ -741,9 +741,13 @@ global
        #  https://hynek.me/articles/hardening-your-web-servers-ssl-ciphers/
        # An alternative list with additional directives can be obtained from
        #  https://mozilla.github.io/server-side-tls/ssl-config-generator/?server=haproxy
-       ssl-default-bind-ciphers ECDH+AESGCM:DH+AESGCM:ECDH+AES256:DH+AES256:ECDH+AES128:DH+AES:RSA+AESGCM:RSA+AES:!aNULL:!MD5:!DSS
-       ssl-default-bind-options ssl-min-ver TLSv1.2
-       tune.ssl.default-dh-param 2048
+  ssl-default-bind-curves X25519:prime256v1:secp384r1
+  ssl-default-bind-ciphers ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:DHE-RSA-CHACHA20-POLY1305
+  ssl-default-bind-ciphersuites TLS_AES_128_GCM_SHA256:TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256
+  ssl-default-bind-options prefer-client-ciphers ssl-min-ver TLSv1.2 no-tls-tickets
+  ssl-default-server-ciphers ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:DHE-RSA-CHACHA20-POLY1305
+  ssl-default-server-ciphersuites TLS_AES_128_GCM_SHA256:TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256
+  ssl-default-server-options ssl-min-ver TLSv1.2 no-tls-tickets

We already discussed it on
https://groups.google.com/g/bigbluebutton-dev/c/ZEBqtxi9Oxo/m/sGvL4VDnAgAJ

[hex-m]

The "modern" configuration that is suggested by Mozilla may be worth considering too? TLS 1.3 has widespread support by now. https://caniuse.com/tls1-3

[Daniel-at-git]

The "modern" configuration that is suggested by Mozilla may be worth considering too? TLS 1.3 has widespread support by now. https://caniuse.com/tls1-3

Also in "modern" configuration TLSv1.3 is on. Or do you suggest to turn TLSv1.2 off? Without TLSv1.2 you can loos some (students/) customer with very old HW. Maybe old smartphones (which can be used for audio connection to BBB) with Android 8.
In practice, it is probably possible to deactivate TLSv1.2 in most cases.