On Fri, Nov 07, 2014 at 10:17:40AM +0100, Lars Heide wrote: > > Please post more detailed logging for this. Was this logged by > > your postfix/smtpd SMTP server or by the postfix/smtp SMTP client? > > Any idea what software the other end was using? ... > > Logged by postfix SMTP server (I redacted specific system information): > > Nov 4 09:00:44 mailserver postfix/smtpd[5708]: connect from > postur.example.com[93.184.216.119] > Nov 4 09:00:44 mailserver postfix/smtpd[5708]: SSL_accept error from > postur.example.com[93.184.216.119]: -1 > Nov 4 09:00:44 mailserver postfix/smtpd[5708]: warning: TLS library > problem: error:140A1175:SSL > routines:SSL_BYTES_TO_CIPHER_LIST:inappropriate fallback:ssl_lib.c:1505: > Nov 4 09:00:44 mailserver postfix/smtpd[5708]: lost connection after > STARTTLS from postur.example.com[93.184.216.119] > Nov 4 09:00:44 mailserver postfix/smtpd[5708]: disconnect from > postur.example.com[93.184.216.119]
Was there a prior connection shortly before that where the handshake failed for some other reason? > They use Kerio Connect 8.4.0 RC 1. According to Wikipedia (couldn't find > any version information on their website): > > 8.3.4 OpenSSL library upgraded to version 1.0.1j to prevent MITM > protocol downgrade to insecure SSL 3.0 protocol Perhaps 1.0.1j sometimes sends SCSV when it should not, I'll look into it when I get a chance. -- Viktor.