The internet has changed to a place where most protocols like HTTP etc now use secure connections with TLS by default. While both HTTP and the MySQL Protocol use TLS for secure connections there are still many differences which make it difficult for MySQL to benefit from the same advancements as HTTP has seen in the last so many years. What is TLS? TLS stands for Transport Layer Security and is the successor of SSL (Socket Layer Security). SSL and TLS are often used interchangably, while this isn’t correct strictly speaking. What TLS provides is a standardized way to encrypt in transit traffic and authenticate the other end of the connection. TLS when used together with HTTP is known as HTTPS, for secure HTTP. How TLS works in HTTPS The client (webbrowser) connects to a server on port 443. Then negitiation is done to agree on what encryption method is to be used. The server presents the client with a certificate, which the client then verifies against the system trust store. For ...

Oracle recently announced a new authentication plugin: caching_sha2_password . This was added in 8.0.4 , the second release candidate for MySQL 8.0. The new plugin is also made the default (can be configured by changing default_authentication_plugin . Why? Phasing out SHA1 As Oracle said in the blog post to annouce this change they want to move to a more secure hashing algorithm ( SHA256 ). Which I think is a good reason to do this. Adding salt Adding a salt makes hashes for identical passwords, but different users different. Again a good reason to do this. Performance Their earlier attempt at this resulted in sha256_password . But this resulted in slower authentication. Without using persistent connections this is a serious limitation. So again a good reason. What's wrong? If you don't use SSL/TLS it gives your password away. To protect against sending the password in cleartext over an insecure connection it encrypts the password before sending it. It does this by ...

In conversations about SSL/TLS people often say that they either don't need TLS because they trust their network or they say it is too slow to be used in production. With TLS the client and server has to do additional work, so some overhead is expected. But the price of this overhead also gives you something in return: more secure communication and more authentication options (client certificates). SSL and TLS have existed for quite a long time. First they were only used for online banking and during authentication on web sites. But slowly many websites went to full-on SSL/TLS. And with the introduction of Let's encrypt many small websites are now using SSL/TLS. And many non-HTTP protocols either add encryption or move to a HTTP based protocol. So TLS performance is very important for day-to-day usage. Many people and companies have put a lot of effort into improving TLS performance. This includes browser vendors, hardware vendors and much more. But instead of just hopi...

Backup traffic After securing application-to-database and replication traffic, you should also do the same for backup traffic. If you use Percona XtraBackup with streaming than you should use SSH to send your backup to a secure location. The same is true for MySQL Enterprise Backup. Also both have options to encrypt the backup itself. If you send your backup to a cloud service this is something you should really do, especially if it is not sent via SSH or HTTPS. And mysqldump and mysqlbinlog both support SSL. And you could use GnuPG, OpenSSL, WinZIP or any other tool to encrypt it. Sending credentials You could try to force the client to send credentials elsewhere. This can be done if you can control the parameters to the mysql client. It reads the config from /etc/my.cnf, ~/.my.cnf and ~/.mylogin.conf but if you for example specify a login-path and a hostname.. it connects to that host, but with the password and username from the loginpath from the encrypted ~/.mylogin.cnf file. ...

The mysql_sha256_password doesn't use the nonce system which is used for mysql_new_password , but instead forces the use of RSA or SSL. This is how that works: The client connects The server changes authentication to sha256 password (or default?) The server sends the RSA public key. The client encrypts the password with the RSA public key and sends it to the server. The server decrypts the password with the private key and validates it. The problem is that the client trusts public key of the server. It is possible to use --server-public-key-path=file_name . But then you need to take care of secure public key distribution yourself. So if we put a proxy between the client and the server and then have the proxy sent its own public key... then we can decrypt it and reencode it with the real public key and send it to the server. Also the decrypted password is the password, not a hash. So we then know the real password. And if SSL is used it doesn't do the RSA encryption....

In my previous blogs I told you to enable SSL/TLS and configure it to check the CA. So I followed my advice and did all that. Great! So the --ssl-mode setting was used a few times as a solution. And it has a setting we didn't use yet: VERIFY_IDENTITY . In older MySQL versions you can use --ssl-verify-server-cert . Both turn on hostname verification. The attack Get any certificate which is trusted by the configured CA, this can for example be a certificate from a development machine. And use that with a man-in-the-middle proxy. Then the client: Checks if SSL is uses ( --ssl-mode=REQUIRED ) Verify if the certificate is signed by a trusted CA ( --ssl-mode=VERIFY_CA ) Both checks succeed. But the certificate might be for testhost01.example.com and the database server might be prod-websitedb-123.example.com. Browsers by default verify hostnames, MySQL does not. Turning on hostname validation So use --ssl-mode=VERIFY_IDENTITY and everything should be fine? Well that might ...

In my previous blogs I told you to enable SSL/TLS and force the connection to be secured. So I followed my advice and did forced SSL. Great! So now everything is 100% secure isn't it? No it isn't and I would never claim anything to be 100% secure. There are important differences in the SSL/TLS implementations of browers and the implementation in MySQL. One of these differences is that your browser has a trust store with a large set of trusted certificate authorities. If the website you visit has SSL enabled then your browser will check if the certificate it presents is signed by a trusted CA. MySQL doesn't use a list of trusted CA's, and this makes sense for many setups. The key difference is that a website has clients (browsers) which are not managed by the same organization. And for MySQL connections the set of clients is often much smaller are more or less managed by one organization. Adding a CA for a set of MySQL connections if ok, adding a CA for groups of web...

Intro In my previous blog post I told you to use SSL/TLS to secure your MySQL network connections. So I followed my advice and did enable SSL. Great! So first let's quickly verify that everything is working. So you enabled SSL with mysql_ssl_rsa_setup , used a OpenSSL based build or put ssl-cert , ssl-key and ssl-ca in the mysqld section of your /etc/my.cnf and now show global variables like 'have_SSL'; returns 'YES'. And you have configured the client with --ssl-mode=PREFERRED . Now show global status like 'Ssl_cipher'; indicates the session is indeed secured. You could also dump traffic and it looks 'encrypted' (i.e. not readable)... With SSL enabled everything should be safe isn't it? The handshake which MySQL uses always starts unsecured and is upgraded to secured if both the client and server have the SSL flag set. This is very similar to STARTTLS as used in the SMTP protocol. To attach this we need an active attack; we need ...

Intro In a set of blog posts I will explain to you how different attacks on the network traffic of MySQL look like and what you can do to secure your systems againt these kinds of attacks. How to gain access To gain access to MySQL network traffic you can use tcpdump, dumpcap, snoop or whatever the tool to capture network packets on your OS is. This can be on any device which is part of the connnection: the server, the client, routers, switches, etc. Besides application-to-database traffic this attack can also be done on replication traffic. Results This allows you to extract queries and result sets. The default password hash type mysql_new_password uses a nonce to protect against password sniffing. But when you change a password this will be sent accross the wire by default. Note that MySQL 5.6 and newer has some protection which ensures passwords are not sent to the logfiles, but this feature won't secure your network traffic. In the replication stream however there are...

I've ran a simple test to see the performance impact of TLS on MySQL connections with MySQL Connector/Python The test results are in this Jupyter notebook . TL;DR: Try to reuse connections if you use TLS Establishing TLS connections is expensive (server & client) Improved performance might be possible in the future by using TLS Tickets Not tested: Difference between YaSSL and OpenSSL Difference between Ciphersuites Performance of larger resultsets and queries

In this blog post I will describe different ways of using SSL with the MySQL database server. What does SSL give you? You might use MySQL replication over the internet or connect to MySQL over the internet. Another posibility is that you connect over an enterprise network to which just too many people have access. This is especially an issue if you use an BYOD network. SSL helps here by encrypting the network traffic to prevent against evesdropping. It also validates that you're talking to the correct server to prevent man-in-the-middle attacks. And you can also use SSL client certificates together with an password as two factor authentication. SSL is not the only option, you could use SSH and many MySQL GUI clients like MySQL Workbench support this. But you can't easily use SSH with a python script or mysqldump. Things that could go wrong Using SSL is almost always better than not using SSL at all. So there is not much you could do wrong. But there are a few things t...

So assume you just uploaded the certificate you use to identify yourself to the MySQL server to Github or some other place it doesn't belong... and there is no undelete . First: Don't panic . Often a password is required besides a certificate to connect to the server. So someone with the certificate can't use it without the password. The certificate itself might be protected by a password, but that's really rare. Also access to MySQL and/or your account should be limited to certain IP's. The next step is to revoke the certificate. This is possible since MySQL 5.6.3 by using a Certificate Revocation List (CRL). A CRL is a list of the serials of the revoked certificates and signed by the CA. So this will only work if the certificates have unique serials. To get the serial of a certificate with OpenSSL: $ openssl x509 -in client-cert.pem -noout -text | grep 'Serial Number'  Serial Number: 3 (0x3) To get the serial of a certificate with GnuTLS: $ ce...

In a comment on my post about Using SSL with MySQL xiaochong zhang asked if it is possible to decode SSL/TLS encrypted MySQL traffic. The short answer is: It depends. To test this we need a MySQL server which is SSL enabled. I used MySQL Sandbox to create a sandboxed 5.6.19 server. Then I used mysslgen to create the config and the certificates. $ make_sandbox 5.6.19 $ ./mysslgen.py --config=sandboxes/msb_5_6_19/my.sandbox.cnf --ssldir=sandboxes/msb_5_6_19/ssl This assumes there already is a extracted tarball of MySQL 5.6.19 in ~/mysql/5.6.19 The mysslgen.py script will return a message with the changes you should make in your mysqld and client sections of the my.sandbox.cnf file. Then restart the server to make it active. For SSL to work we need to connect using TCP/IP instead of over a UNIX socket. So we connect with "./my sql -h 127.0.0.1". Now execute "\s" or "status" to see if we're indeed using SSL. It probably looks like this: mys...

I've blogged before about how complicated setting up SSL with MySQL can be. Since then many bugs have been fixed related to SSL. But still many people are using unencrypted connections for replication and client connections. This could be because of possible performance degradation. But then it could be used for only the admin connections. It could also be because they already use SSH or VPN. But for many it's because they think it's complicated. This is not necessary. I've created mysslgen which makes it easier to setup SSL. Just run mysslgen.py and then the CA, server and client certificates and keys will be generated for you. The most difficult part it to get python 3.3 or python 2.7 to run on CentOS/RHEL/OEL 6. If you think SSL should be part of the default MySQL installation, then click the 'Affects me' button for Bug #70734 . During the creation of mysslgen I found out MySQL fails to load private keys if they are in PKCS#8 format ( Bug #71271 ...

Since MySQL 4.0 it's possible to use SSL to secure the connections to MySQL. Unfortunately this is not used very often. It can be used for cient-server connections and for replication . It will encrypt your traffic and prevent man-in-the-middle attacks if you're using ssl-verify-server-cert when connecting using mysql. Securing database communication can be required to be compliant to some regulations. There are other means of preventing anyone from snooping your database traffic like VPN, SSH Tunneling or stunnel. As usual the documentation is quite good. The only issue with the docs is that the verification step is missing. ( Bug #59628 ). I'ts quite hard to debug as the OpenSSL messages are not reported in MySQL's errors. Bug luckily that's changing as Bug #21287 does have a patch under SCA/OCA. And you should check your my.cnf for typo's when it's not working as mysqld won't tell you when it can't find the ssl-ca file. ( Bug #59630 ). I'v...