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Since I upgraded my PC from (k)ubuntu 12.04 to 12.10 I receive this error message when trying to send an email using sendemail.

Installing an older version of IO::Socket::SSL is not an option. I have the impression that all works as it should and the message is just a warning.

How can I get rid of this message?


I think the below has to do with the problem (/usr/share/perl5/IO/Socket/SSL.pm).

34  use constant DEFAULT_VERSION     => 'SSLv23:!SSLv2';


251         my %default_args = (
252                 Proto => 'tcp',
253                 SSL_server => $is_server,
254                 SSL_use_cert => $is_server,
255                 SSL_check_crl => 0,
256                 SSL_version     => DEFAULT_VERSION,
257                 SSL_verify_mode => SSL_VERIFY_NONE,
258                 SSL_verify_callback => undef,
259                 SSL_verifycn_scheme => undef,  # don't verify cn
260                 SSL_verifycn_name => undef,    # use from PeerAddr/PeerHost
261                 SSL_npn_protocols => undef,    # meaning depends whether on server or client side
262                 SSL_honor_cipher_order => 0,   # client order gets preference
263         );


332         ${*$self}{'_SSL_ctx'} = IO::Socket::SSL::SSL_Context->new($arg_hash) || return;


And at sendemail end I think it is about here in the code:

1903     ## Start TLS if possible
1904     if ($conf{'tls_server'} == 1 and $conf{'tls_client'} == 1 and $opt{'tls'} =~ /^(yes|auto)$/) {
1905         printmsg("DEBUG => Starting TLS", 2);
1906         if (SMTPchat('STARTTLS')) { quit($conf{'error'}, 1); }
1907         if (! IO::Socket::SSL->start_SSL($SERVER, SSL_version => 'SSLv3 TLSv1')) {
1908             quit("ERROR => TLS setup failed: " . IO::Socket::SSL::errstr(), 1);
1909         }
1910         printmsg("DEBUG => TLS: Using cipher: ". $SERVER->get_cipher(), 3);
1911         printmsg("DEBUG => TLS session initialized :)", 1);
1913         ## Restart our SMTP session
1914         if (SMTPchat('EHLO ' . $opt{'fqdn'})) { quit($conf{'error'}, 1); }
1915     }
1916     elsif ($opt{'tls'} eq 'yes' and $conf{'tls_server'} == 0) {
1917         quit("ERROR => TLS not possible! Remote SMTP server, $conf{'server'},  does not support it.", 1);
1918     }
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Solved it for the time being by changing 'SSLv3 TLSv1'in sendemail line 1907 to 'SSLv3', but editing files installed from a package is bad. – jippie Oct 29 '12 at 19:43
up vote 6 down vote accepted

There is a bug report on Debian's bug tracker website: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=679911

It also states a workaround:

specify -o tls=no as an option on the command line.

Thanks @Manolo Díaz on debian.org.

share|improve this answer

Easier workaround is:




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Worked like a charm, thanks Nguli – NguliMkaree Dec 10 '13 at 9:16
My problem is that this fix breaks Net::Twitter – Dave Jacoby Nov 19 '14 at 16:40
1690 line /usr/share/perl5/IO/Socket/SSL.pm in Ubuntu 14.04 – Rahul Patil Jan 15 '15 at 7:08
Since some people still consider the workaround in this answer as the fix and complain about the bug in IO::Socket::SSL: The problem is not in IO::Socket::SSL but is a bug in sendEmail, which is unmaintained since 2009. In detail: the syntax for SSL_version is wrong and was not even valid at the time code was written, only IO::Socket::SSL did not complain then. The fix is just to remove the setting of SSL_version from sendemail. See also rt.cpan.org/Public/Bug/Display.html?id=77401. – Steffen Ullrich Sep 6 '15 at 6:23

Also a workaround, do this if it's required to send from smtp.gmail.com:

/usr/bin/sendemail on line 1907: 'SSLv3 TLSv1' => 'SSLv3' 

as temporary solution.

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If you still get a certificate error after fixing the SSLversion as shown above, you need to disable certificate checking:

if (! IO::Socket::SSL->start_SSL($SERVER, SSL_version => 'SSLv23:!SSLv2', SSL_verify_mode => 0)) {
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Haven't seen the issue myself for ages and the ubuntu package has been fixed in the mean while. First attempt into fixing this issue should be to patch the system / use most current versions of the software. The alternative solution is interesting from an other point of view though, thnx. – jippie Jan 15 at 19:12

Actually, just take the default (remove the second parameter). See https://metacpan.org/pod/IO::Socket::SSL (search for SSL_version). The default is SSLv23:!SSLv3:!SSLv2.

I modified line 1906 in v1.56 to read

#        if (! IO::Socket::SSL->start_SSL($SERVER, SSL_version => 'SSLv3 TLSv1')) {
    if (! IO::Socket::SSL->start_SSL($SERVER)) {

(just commenting out the original line)

share|improve this answer
if (! IO::Socket::SSL->start_SSL($SERVER, SSL_version => 'SSLv3')) {<br>

works on debian wheezy with sendEmail 1.56-2 and libio-socket-ssl-perl 1.76-2 and

if (! IO::Socket::SSL->start_SSL($SERVER, SSL_version => 'SSLv23:!SSLv2')) {<br>

works with …/IO/Socket/SSL.pm: 1.74 sendEmail: 1.56 in Ubuntu.

This has been a problem in ubuntu and debian repos for over a year.

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To fix this, I edited sendEmail-v1.55 at line 1884 to change 'SSLv3 TLSv1' to 'SSLv3'.

OSX 10.10.1

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