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1answer
43 views

How to mitigate STARTTLS MITM (downgrading and forged certificates) between email servers?

I'm not as technically inclined as most on this site so please keep that in mind. I wanted to learn more about email security so I did some research and everything is according to my understanding, ...
0
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0answers
25 views

How to make Postfix SMTP TLS Optional?

Just did an [emergency] conversion from qmail to postfix last night - but now I'm getting people complaining that mail client errors are showing up stating "no available encryption methods available" ...
0
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0answers
102 views

Dovecot STARTTLS fails using fetchmail

I currently try to get my own mail server up and running. So far everything seems fine as I am able to connect to this mailserver using thunderbird. The only thing I have to do is accepting my own ...
1
vote
1answer
26 views

Verify TLS encryped communication when querying LDAP server?

I have a web application (not hosted on windows) that authenticates users by querying an LDAP server (a windows domain controller). The app is configured to use STARTTLS to encrypt communication with ...
-1
votes
1answer
39 views

Gitlab with OpenLDAP secured with TLS

I have a working, secure OpenLDAP server running at: auth.<company name>.com I also have a reader account that Gitlab can use: cn=Reader Reader,ou=users,dc=auth,dc=<Company ...
0
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1answer
34 views

SMTP doesn't work on distinct machine [closed]

I'm trying to setup TLS e-mail on remote machine, but it doesn't work. Trying to send e-mail on my local machine (Windows 7 x64 locale ru-ru): 16:33:18 CONNECT : Looking up host name ...
0
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1answer
323 views

Postfix STARTTLS only on port 25

I want to enable STARTTLS on port 25, but for unknown reasons it only works on port 465. master.cf: smtp inet n - - - - smtpd -o syslog_name=postfix/smtp -o ...
1
vote
1answer
178 views

How to disable SSLv3 in Postfix 2.11?

I just noticed (by some online check tools) that my mailserver may allow SSLv3 and updated my configuration. My current config in Postfix 2.11.2: # inbound smtpd_tls_security_level = may ...
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0answers
189 views

LDAP with TLS: connect error(-11)

I configured OpenLDAP and today I've configured the TLS for more security following these guide lines: Configure OpenLDAP with TLS=required Modifying the cn=config.ldif with config file: dn: ...
3
votes
1answer
682 views

Postfix Recipient address rejected: Access denied Error

Trying to use zend mail smtp to send email from my php app login authenticated and give me this constant error I don't have to deal with I look into de 36 question here on serverfault.com changing ...
2
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0answers
166 views

Does Google require TLS on port 587? Exchange 2010 SMTP has mail sent to GMAIL backed up in queue

Exchange 2010 SMTP has mail backed up in queue. Any email sent to Gmail sits in the queue while any email sent to another personal domain which has email filtering enabled errors, "asp.reflexion.net ...
3
votes
0answers
50 views

How can I explicitly disable TLS when sending to one specific recipient?

I have a SendMail 8.14 server deployed in the middle of an SMTP workflow (Outbound mail looks like Exchange -> SendMail -> Appliance -> Internet) I have TLS configured for the first three hosts. ...
0
votes
1answer
89 views

starttls fails after IP address change

I have changed the IP address of our exim mail server (the virtual machine has been copied to a different host, also the network configuration is using NAT). Now it no longer accepts STARTTLS ...
1
vote
1answer
129 views

How can I explicitly force SendMail to not use SSLv3 for STARTTLS connections?

SendMail 8.14.x With SSLv3 being sunset (to put it lightly), I'd like to ensure that my SendMail servers aren't using it when establishing STARTTLS connections. Is there a way I can force SendMail to ...
0
votes
0answers
152 views

What does “version=TLSv1/SSLv3” mean in SendMail STARTTLS log output?

SendMail 8.14.x I have a Sendmail server configured to use TLS and I see TLS log entries like the following: Oct 25 04:04:04 foobox sendmail[1234] STARTTLS=client, relay=[1.1.1.1], version ...
0
votes
1answer
129 views

Exim says “The request is invalid” during gnutls_handshake

I have Debian wheezy and setup Exim to listen to port 587, where users can authenticate using TLS. I'm testing it with Thunderbird 31.1.2. When I try to send a message, Thunderbird displays this: ...
0
votes
1answer
140 views

postfix cannot communicate with target server via TLS/SSL

I am able to connect my postfix server with TLS. All things are set up. But when i send a message with this secure connection, target server (for example gmail) receive my message without TLS/SSL ...
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votes
1answer
25 views

no STARTTLS in inbound email to exim [closed]

I have a CentOS VPS and I'm using Exim 4.7.2 For some days I have an issue in Thunderbird and in other client because seems STARTTLS not work in incoming email only outgoing e-mail. How can I fix ...
0
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0answers
243 views

Perdition IMAP proxy not using STARTTLS with Cyrus IMAP server

I have a Perdition proxy server setup to forward users to one of two Cyrus backend mailstores based on an LDAP query. Everything works fine except for securing the connection between Perdition and ...
12
votes
2answers
431 views

Is it still “wrong” to require STARTTLS on incoming SMTP messages

According to the STARTTLS Spec Section 5: A publicly-referenced SMTP server MUST NOT require use of the STARTTLS extension in order to deliver mail locally. This rule prevents the STARTTLS ...
0
votes
0answers
130 views

ejabberd and LDAP authentication using StartTLS

I am trying to setup ejabberd that authenticates users against an LDAP server. The LDAP server requires all clients to connect via StartTLS (olcSecurity: tls=1). ejabberd's LDAP module does not ...
0
votes
3answers
1k views

Exim after Thunderbird update: “Could not negotiate a supported cipher suite” [closed]

Recently, after I installed updates on my Kubuntu 14.04. system and a new version of thunderbird was installed, I could not send emails any more. It prompts: Sending of message failed. The message ...
0
votes
1answer
2k views

Postfix still complains that “certificate verification failed” even when “smtp_tls_security_level = fingerprint”

I'm attempting to use Postfix (version 2.6.6 on RHEL6) to connect to and send mail via a mail relay on our internal network. I want to connect with STARTTLS on port 25 (port 465 is not available on ...
2
votes
1answer
463 views

How can I enforce TLS in sendmail when I don't necessarily know the hostname of the downstream MTA (only IPs)? [e.g. by recipients' domain]

I'm running SendMail 8.14 and have some custom static routes for sending to certain domains. These domains are "internal" but not managed directly by me. Here's an example of ...
0
votes
1answer
207 views

SMTP Connection disconnecting after “STARTTLS”

We're having issues with our mail server. Basically some emails from external networks are not being accepted by the mailserver. After some debugging using telnet and looking through the logfiles, it ...
3
votes
2answers
2k views

ejabberd starttls_required in c2s/s2s and disable SSLv3 + unsecure Ciphers

I'm using ejabberd on Ubuntu. My configuration looks like this: {5269, ejabberd_s2s_in, [ {shaper, s2s_shaper}, {max_stanza_size, 131072}, ...
0
votes
0answers
418 views

Storing GPG keys in LDAP with TLS using gpgme

I'm trying to send my GPG public key to our LDAP server, but I'm hitting a wall. My LDAP server only allows LDAP with Start_TLS over port 389, or LDAPS on port 636. I've got the following lines in my ...
8
votes
4answers
12k views

Is STARTTLS more safe than TLS/SSL?

In Thunderbird (and I assume in many other clients, too) I have the option to choose between "SSL/TLS" and "STARTTLS". As far as I understand it, "STARTTLS" means in simple words "encrypt if both ...
1
vote
0answers
245 views

Postfix - SASLAuthentication Problems Cram-MD5 with StartTLS

Recently I configured my mail server which uses Postfix and Courier. Everything works except for the authentication when sending mail via my Postfix server(running on port 587) which has StartTLS ...
0
votes
2answers
6k views

Postfix & Gmail: Authentication Required error

I configured Postfix using this guide. When I send a test E-Mail I get the following error message: May 23 15:36:26 VM11 postfix/smtp[15321]: connect to smtp.gmail.com[2a00:1450:4001:c02::6d]:587: ...
1
vote
1answer
89 views

How can I tell if my LDAP authentications are using StartTLS?

I'm setting up a new OpenLDAP server on Ubuntu 12.04 with a copy of our current LDAP database. I've gotten most of the configuration down, I think, but I'm having trouble telling if the LDAP queries ...
1
vote
2answers
2k views

Does Exchange 2010 encrypt inbound and outbound email traffic by default?

The higher ups have recently asked about this as I'm sure there are compliance issues that need to be addressed. I was under the assumption that Exchange uses opportunistic TLS or StartTLS to try to ...
0
votes
1answer
4k views

TLS: hostname does not match CN in peer certificate

im trying to connect LDAP over StartTLS but Im stuck with an issue. I've followed step by step this guide https://help.ubuntu.com/12.04/serverguide/openldap-server.html#openldap-tls and LDAP it's ...
5
votes
1answer
993 views

postfix TLS configuration for incoming gmx-mail

I set up my mailserver with postfix 2.7.1 and dovecot 1.2.15 and everything seemed to work just fine, but now I found out that people using @gmx.net addresses cannot send emails to me and rather ...
0
votes
1answer
2k views

postfix, TLS and rapidssl - “verify error:num=19:unable to get local issuer certificate”

I have a certificate from rapidssl. I run this command: openssl s_client -showcerts -connect smtp.server.com:465 I get this error: verify error:num=19:self signed certificate in certificate chain ...
2
votes
2answers
397 views

How do I log tls-encrypted smtp traffic?

I'd like to know what my local postfix says to the Amazon SES smtpd after the STARTTLS. In plain text, so I can understand it. Amazon SES requires TLS, so I can't temporarily turn it off. I currently ...
2
votes
2answers
2k views

SMTP server requires STARTTLS

I am using fetchmial. Below is my configuration. I want the retrieved emails to be sent to my gmail address. But I encountered an error below. Could someone help me with this? Thank you in advance. ...
1
vote
2answers
8k views

Postfix Send Error: Must Issue STARTTLS command

Running Ubuntu 12.04 and trying to configure postfix to relay send and receive through GMAIL. Am running into connection issues particularly with TLS. Have tried a bunch of troubleshooting solutions ...
0
votes
1answer
231 views

Configuring postfix to use TLS for a particular server?

Running kubuntu 10.04 on my host, let's call it alpha. I've got postfix as my system MTA. I've got crons running on alpha that need to send email to a remote host, let's call it mailhost. I cannot ...
1
vote
2answers
2k views

How can I ensure Liferay uses TLS for authentication

Please note, this is about communication between Liferay and the LDAP server, not communication between the user's browser and Liferay I'm asking this here since I got zero views (other than my own) ...
5
votes
3answers
242 views

Is a self signed cerificate secure from man in the middle once you have accepted it

I have a mail server that has a self signed SSL certificate. I use Thunderbird to access this server, and it asks me to accept this certificate. So lets say I accept this in a semi secure location, ...
1
vote
2answers
996 views

slapd with STARTTLS only doesn't work

I'm using slapd under Debian/Squeeze and trying to configure the system to only allow TLS-encrypted connections using STARTTLS on port 389. So I've configured my /etc/default/slapd to listen on port ...
0
votes
1answer
2k views

How secure is using “Normal password” for SMTP with connection type = STARTTLS?

I'm using an email client for the first time - for the most part I've always used gmail via the web interface. Now I'm setting up thunderbird to connect to an email server of my own (on my own server, ...
1
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2answers
2k views

lost connection after STARTTLS: Postfix

I've setup a Postfix + Courier server and have a Rails app configured with the SMTP server settings. Whenever the Rails app tries to send an email, this is what appears in the Postfix log (additional ...
1
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2answers
390 views

Handling http and https requests using a single port with lihgttpd

At the moment I am using http and https as different port. And based on request uri, I made a redirection rule from http to https switch and vice versa. But If I can use only a single port for https ...