Transport Layer Security is a cryptographic protocol for encrypting and authenticating network communications, and replaces SSL. It is commonly used to secure Internet protocols such as HTTP.

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Functional implications of differences in SSL and TLS

I know that TLS is essentially a newer version of SSL, and that it generally supports transitioning a connection from unsecured to secured (commonly through a STARTTLS command). What I don't ...
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5answers
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What are the exact protocol level differences between SSL and TLS?

This is a technical deep dive after this overview question was asked. What are the protocol differences between SSL and TLS? Is there really enough of a difference to warrant a name change? (versus ...
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4answers
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Does HTTPS use TCP or UDP?

Does HTTPS use TCP or UDP?
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1answer
13k views

How to inspect remote SMTP server's TLS certificate?

We have an Exchange 2007 server running on Windows Server 2008. Our client uses another vendor's mail server. Their security policies require us to use enforced TLS. This was working fine until ...
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3answers
8k views

Fixing BEAST vulnerability on Apache 2.0 running on RHEL 4

I have a web server running Apache 2.0 on RHEL4. This server recently failed a PCI scan. Reason: SSLv3.0/TLSv1.0 Protocol Weak CBC Mode Vulnerability Solution: This attack was identified in 2004 and ...
11
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1answer
16k views

How to enable TLS 1.1, 1.2 in IIS 7.5

We want to support web browsers utilizing TLS 1.1 and 1.2, which has been apparently implemented by Microsoft, but is turned off by default. So I went searching on Google and discovered some pages ...
10
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5answers
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Do any well-known CAs issue Elliptic Curve certificates?

Background I've seen that Comodo has an elliptic curve root ("COMODO ECC Certification Authority"), but I don't see mention of EC certificates on their web site. Does Certicom have intellectual ...
8
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1answer
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How to disable SSLCompression on Apache httpd 2.2.15? (Defense against CRIME/BEAST)

I read about the CRIME attack against TLS Compression (CVE-2012-4929, CRIME is a successor to the BEAST attack against ssl & tls), and I want to protect my webservers against this attack by ...
8
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1answer
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How to disable TLS 1.1 & 1.2 in Apache?

I have an Ubuntu 12.04.2 LTS server running Apache 2.2.22 with mod_ssl and OpenSSL v1.0.1. In my vhosts config (everything else within which behaves as I would expect), I have the SSLProtocol line ...
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3answers
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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 ...
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5answers
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What is TLS and how does it compare to SSL?

Is TLS the "new" version of SSL? What features does it add, or security issues does it address? Can anything that supports SSL support TLS? What would be involved in making the switch? Is the ...
7
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1answer
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Safest ciphers to use with the BEAST? (TLS 1.0 exploit) I've read that RC4 is immune

Now that the BEAST is public knowledge, TLS 1.0 is NOT safe to use (nor is SSL 3.0). I have seen reports that the RC4 cipher is unaffected (and is widely supported). Is that true? I know that TLS 1.1 ...
7
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2answers
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Configure OpenLDAP with TLS=required

Nowadays, OpenLDAP needs to be configured with ldapmodify cn=config, as describe here. But nowhere I can find how you configure it to only accept TLS traffic. I just confirmed that our server accepts ...
7
votes
1answer
39 views

How widely supported is forced TLS on inbound SMTP connections?

I run an MTA consisting of the standard Postfix, SpamAssassin, ClamAV, SPF/DKIM checks etc. This MTA is used for inbound email only, doesn't host any accounts and forwards any mail that passes said ...
6
votes
2answers
769 views

Display a TLS icon for messages that are TLS secured (Outlook)

One of my colleagues at a large financial institution has customised Lotus Notes to show a TLS icon for messages that are TLS secured. I'm interested in imitating this feature in Outlook, and believe ...
6
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3answers
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What's the difference between: Verisign Thawte Geotrust Rapidssl certs?

Verisign owns all these certificate issuing companies: Verisign Thawte Geotrust and Rapidssl. What is the difference between them and why is the price difference so great? Update: Here are just a ...
6
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3answers
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Require TLS on RDP for all connections

I have a 2008 DC and a 2008 AD CS server and a Windows 7 client. What I would like is to require the certificate to be used when RDPing to the server. The certificate is valid, and if I connect ...
6
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4answers
7k views

Disable SMTP AUTH on Port 25

Due to PCI-DSS, we are required to disable plaintext authentication. We've achieved this by encapsulating communications between our mail server and clients with TLS on port 465. The problem lies in ...
6
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2answers
2k views

Overhead of TLS/SSL on a TCP socket connection?

Is there any bandwidth overhead on using SSL on a TCP connection? I understand, of course, the processing/memory usage overhead in encrypting and decrypting packets, but as far as bandwidth is ...
6
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1answer
3k views

Third Party Wildcard Certificates for use with Microsoft NPS / RADIUS / PEAP

I want to replace the SSL certificate that is used for PEAP on our NPS server that is doing RADIUS authentication for our Cisco WLCs. The current certificate is a SSL certificate that does Client ...
6
votes
4answers
3k views

SSL connection errors from Apache

I'm running a (self-signed) SSL cert site on Apache/2.2.14 on Ubuntu 10.04, but various browsers are giving errors on half the connection attempts. Just now saw this transient error from Chrome: ...
5
votes
2answers
6k views

SSLCipherSuite - disable weak encryption, cbc cipher and md5 based algorithm

A developer recently ran a PCI Scan with TripWire against our LAMP server. They identified several issues and instructed the following to correct the issues: Problem: SSL Server Supports Weak ...
5
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1answer
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Postfix TLS over SMTP - RCPT TO prompts renegotiation then 554 5.5.1 Error: no valid recipients

I've setup ispconfig3 on my debian six server, and here is a little smtp over ssl: The server is postfix AUTH PLAIN (LOL!) 235 2.7.0 Authentication successful MAIL FROM: lol@lol.com 250 2.1.0 Ok ...
5
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2answers
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detect weak encryption and outdated protocols

I'm looking for software that helps detecting applications that use weak encryption or outdated protocols in a central place. Sorry if that sounds vague. Maybe an example will help. Let's take a ...
5
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2answers
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SSL/TLS Cipher Priority

I am working on trying to make sense of what is required for both PCI DSS compliance as well as FIPS compliance in relation to SSL/TLS cipher suites. I have been reading the guide here and here. ...
5
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2answers
1k views

Exchange 2007 Cipher Suite Order

I'm experiencing issues receiving TLS encrypted e-mail from a specific domain. We entered into an agreement to use a 256-bit cipher and apparently our Exchange 2007 server on Windows Server 2003 ...
5
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2answers
3k views

Secure LDAP Authentication with Active Directory

We are working on a web project where we need to be able to bind to an active directory domain and then pass the user's credentials to the domain to make sure the user has successfully authenticated ...
5
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2answers
2k views

Why does IE think that my certificate is invalid?

I have my chained certificate from Dreamhost set up and working for all browsers. I have 2 sites with 2 certs from dreamhost, example.com and sub.example.com. All browsers are fine with the certs on ...
5
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5answers
396 views

Is the world ready for name based HTTPS vhost service? [duplicate]

Possible Duplicate: Multiple SSL domains on the same IP address and same port? I'm developing a web app that MUST MUST MUST use HTTPS. It's kinda developed on the cheap though, and I really ...
5
votes
3answers
456 views

Monit failing to connect to Dovecot over SSL IMAP

I run Monit to keep check on processes on a Debian server. It's working as normal for all other services (Apache SSL, Postfix, SSH etc.) but Monit's checks on Dovecot are failing repeatedly. I think ...
4
votes
2answers
533 views

How can I verify if TLS 1.2 is supported on a remote web server from the RHEL/CentOS shell?

I'm on CentOS 5.9. I'd like to determine from the linux shell if a remote web server specifically supports TLS 1.2 (as opposed to TLS 1.0). Is there an easy way to check for that? I'm not seeing a ...
4
votes
3answers
3k views

Failed tls handshake. Does not contain any IP SANs

I'm trying to set up logstash forwarder, but I have issues with making a proper secure channel. Trying to configure this with two ubuntu (server 14.04) machines running in virtualbox. They are 100% ...
4
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4answers
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Server suddenly running out of entropy [solved, sort of]

Since a reboot yesterday, one of our virtual servers (Debian Lenny, virtualized with Xen) is constantly running out of entropy, leading to timeouts etc. when trying to connect over SSH / TLS-enabled ...
4
votes
1answer
92 views

Is it possible to configure IIS to redirect based on the SSL cipher suite used for the connection?

With the announcement of POODLE, I would like my servers to accept SSL3.0 connections but have them serve a page which indicates that the user should update to a newer browser with TLS support. It ...
4
votes
1answer
1k views

Exim TLS and Secure SMTP

I'm in the process of converting an existing mail server to support encrypted SMTP for our clients, but I've run into this brick wall with very little useful log data to help me forward. Everything ...
4
votes
1answer
36 views

Perfect Forward Secrecy (PFS) for mail servers

Perfect Forward Secrecy is an important enhancement to SSL/TLS communications, helping prevent captured SSL traffic from being decrypted even if the attacker has the private key. It's easy enough to ...
4
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3answers
406 views

Should web farms be concerned with TLS handshake overhead

I have a web farm where the web servers are responsible for negotiating the secure connections. Does anyone else with a web farm go out of their way to reduce TLS handshake overhead by ensuring that ...
4
votes
1answer
785 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 ...
4
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2answers
496 views

Is there a way to make TLS work with rsyslog in Ubuntu 12.04?

I configure rsyslog to load the TLS module (to talk to loggly) and I'm getting this error: Jun 20 13:14:00 feynman rsyslogd-2068: could not load module '/usr/lib/rsyslog/lmnsd_gtls.so', rsyslog error ...
4
votes
2answers
2k views

OpenLdap TLS authentication setup

I am trying to setup openldap on ubuntu 12.04 by following this guide https://help.ubuntu.com/12.04/serverguide/openldap-server.html When I tried to enable TLS on the server by creating a self signed ...
4
votes
1answer
436 views

Apache won't upgrade connection to TLS

I have written a IPP server in PHP running under Apache. With the standard IPP clients it works just fine. But when I try to print from an iOS device the connections breaks when the client tries to ...
4
votes
1answer
635 views

Securing MONGO with TLS (and mutual TLS)

Following instructions outlined in MongoDB SSL encryption and Spring's Driver, I got 2.1.0 and after building it, it says it doesn't recognize sslOnNormalPorts, sslPEMKeyFile or sslPEMKeyPassword. ...
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5answers
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LDAP over SSL/TLS working for everything but login on Ubuntu

I have gotten OpenLDAP with SSL working on a test box with a signed certificate. I can use an LDAP tool on a Windows box to view the LDAP over SSL (port 636). But when I run dpkg-reconfigure ...
3
votes
2answers
196 views

Security of a self-signed certificate

If I verify the fingerprint of a self-signed SSL certificate on the client, can a man-in-the-middle attack still occur?
3
votes
3answers
115 views

Postfix and compromised accounts

First of all, sorry for my English. I think it's very common to set the permit_mynetworks and permit_sasl_authenticated restrictions on first positions of the smtpd_recipient_restriction list, but, ...
3
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1answer
9k views

Disable SSL / TLS compression in Apache 2.2.x

Is there a way to disable SSL/TLS Compression in Apache 2.2.x when using mod_ssl? If not, what are people doing to mitigate the effects of CRIME/BEAST in older browsers? Related Links: ...
3
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1answer
133 views

Is there a low cost certificate authority that is generally accepted for TLS over SMTP? [closed]

I'm getting ready to enable TLS on my Postfix servers. I am doing this as a result of being told that there are some sending servers that refuse to send messages if TLS is not available. Since I ...
3
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3answers
7k views

How do I limit SSL/TLS connections to at least 128-bit encryption?

When I'm ordering an SSL cert for my public web server, how can I be sure that the web server (IIS 6 in my case) will only allow SSL/TLS client connections supporting our corporate standard of at ...
3
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3answers
1k views

What books will help me learn everything I can about SSL/PKI?

Since SSL is the backbone of the internet, (now technically called TLS), what are some good books I should read up on to understand all aspects of it. I suppose I'll need to learn some math, some PKI ...
3
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3answers
1k views

What percentage of web users are running on browsers/OSes that support SNI? [closed]

Has anyone done any analysis (or know where I can find some!) on what proportion of internet users are using a browser/operating system combination that support SNI (Server Name Indication) SSL/TLS ...