Good tip!.
A bit off topic, but nice to know:
if you have webmail enabled on your mailserver, you can simply remove all protocols and add just the wanted protocols for apache:
-ALL, +TLSv1.2
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# SSL Protocol support:
# List the enable protocol levels with which clients will be able to
# connect. Disable SSLv2 access by default:
#SSLProtocol all -SSLv2 -SSLv3
#SSLProtocol all -SSLv2 -SSLv3 -TLSv1 -TLSv1.1
SSLProtocol -ALL +TLSv1.2
Tip, if you have an old mobile phone, you need to add '+TLSv1', to be able to use Zpush or just buy a new phone that supports TLSv1.2
To test your mailserver's SSL can use:
https://www.ssllabs.com/ssltest/
A decent firewall will/should block (most) SSL vulnerabilties.
To be able to check SSL use testssl script to check all servers
https://github.com/drwetter/testssl.sh
Create some dir (/root/software)
cd /root/software
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git clone --depth 1 https://github.com/drwetter/testssl.sh.git
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./testssl.sh --vulnerable <<hostname>>
result
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rDNS (redacted): EFA3 .
Service detected: HTTP
Testing vulnerabilities
Heartbleed (CVE-2014-0160) not vulnerable (OK), timed out
CCS (CVE-2014-0224) not vulnerable (OK)
Ticketbleed (CVE-2016-9244), experiment. not vulnerable (OK), session IDs were returned but potential memory fragments do not differ
ROBOT not vulnerable (OK)
Secure Renegotiation (CVE-2009-3555) not vulnerable (OK)
Secure Client-Initiated Renegotiation not vulnerable (OK)
CRIME, TLS (CVE-2012-4929) not vulnerable (OK)
BREACH (CVE-2013-3587) no HTTP compression (OK) - only supplied "/" tested
POODLE, SSL (CVE-2014-3566) not vulnerable (OK)
TLS_FALLBACK_SCSV (RFC 7507) No fallback possible, no protocol below TLS 1.2 offered (OK)
SWEET32 (CVE-2016-2183, CVE-2016-6329) not vulnerable (OK)
FREAK (CVE-2015-0204) not vulnerable (OK)
DROWN (CVE-2016-0800, CVE-2016-0703) not vulnerable on this host and port (OK)
no RSA certificate, thus certificate can't be used with SSLv2 elsewhere
LOGJAM (CVE-2015-4000), experimental not vulnerable (OK): no DH EXPORT ciphers, no DH key detected with <= TLS 1.2
BEAST (CVE-2011-3389) no SSL3 or TLS1 (OK)
LUCKY13 (CVE-2013-0169), experimental potentially VULNERABLE, uses cipher block chaining (CBC) ciphers with TLS. Check patches
RC4 (CVE-2013-2566, CVE-2015-2808) no RC4 ciphers detected (OK)
Client check to be sure
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./testssl.sh --client-simulation <<hostname>>
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Running client simulations (HTTP) via sockets
Android 4.2.2 No connection
Android 4.4.2 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
Android 5.0.0 TLSv1.2 ECDHE-RSA-AES128-GCM-SHA256, 256 bit ECDH (P-256)
Android 6.0 TLSv1.2 ECDHE-RSA-AES128-GCM-SHA256, 256 bit ECDH (P-256)
Android 7.0 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
Chrome 65 Win 7 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
Chrome 70 Win 10 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
Firefox 59 Win 7 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
Firefox 62 Win 7 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
IE 6 XP No connection
IE 7 Vista No connection
IE 8 Win 7 No connection
IE 8 XP No connection
IE 11 Win 7 TLSv1.2 ECDHE-RSA-AES256-SHA384, 256 bit ECDH (P-256)
IE 11 Win 8.1 TLSv1.2 ECDHE-RSA-AES256-SHA384, 256 bit ECDH (P-256)
IE 11 Win Phone 8.1 TLSv1.2 ECDHE-RSA-AES256-SHA, 256 bit ECDH (P-256)
IE 11 Win 10 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
Edge 13 Win 10 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
Edge 13 Win Phone 10 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
Edge 15 Win 10 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
Opera 17 Win 7 TLSv1.2 ECDHE-RSA-AES256-SHA, 256 bit ECDH (P-256)
Safari 9 iOS 9 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
Safari 9 OS X 10.11 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
Safari 10 OS X 10.12 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
Apple ATS 9 iOS 9 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
Tor 17.0.9 Win 7 No connection
Java 6u45 No connection
Java 7u25 No connection
Java 8u161 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
Java 9.0.4 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
OpenSSL 1.0.1l TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
OpenSSL 1.0.2e TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
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