Date: Thu, 30 Apr 2015 11:50:25 -0400 From: Jon Oberheide <jon@...rheide.org> To: oss-security@...ts.openwall.com Cc: ocert-announce@...ts.ocert.org, bugtraq@...urityfocus.com Subject: Re: [oCERT-2015-003] MySQL SSL/TLS downgrade Some additional silly links related to the vulnerability: http://backronym.fail/ https://www.duosecurity.com/blog/backronym-mysql-vulnerability And actually one useful link from Todd Farmer: http://mysqlblog.fivefarmers.com/2015/04/29/ssltls-in-5-6-and-5-5-ocert-advisory/ On Wed, Apr 29, 2015 at 10:00 AM, Andrea Barisani <lcars@...rt.org> wrote: > > #2015-003 MySQL SSL/TLS downgrade > > Description: > > The MySQL project is an open source relational database management system. > > A vulnerability has been reported concerning the impossibility for MySQL > users > (with any major stable version) to enforce an effective SSL/TLS connection > that would be immune from man-in-the-middle (MITM) attacks performing a > malicious downgrade. > > While the issue has been addressed in MySQL preview release 5.7.3 in > December > 2013, it is perceived that the majority of MySQL users are not aware of > this > limitation and that the issue should be treated as a vulnerability. > > The vulnerability lies within the behaviour of the '--ssl' client option, > which on affected versions it is being treated as "advisory". Therefore > while > the option would attempt an SSL/TLS connection to be initiated towards a > server, it would not actually require it. This allows a MITM attack to > transparently "strip" the SSL/TLS protection. > > The issue affects the ssl client option whether used directly or triggered > automatically by the use of other ssl options ('--ssl-xxx') that imply > '--ssl'. > > Such behavior is clearly indicated in MySQL reference manual as follows: > > For the server, this option specifies that the server permits but does > not require > SSL connections. > > For a client program, this option permits but does not require the > client to > connect to the server using SSL. Therefore, this option is not > sufficient in > itself to cause an SSL connection to be used. For example, if you > specify this > option for a client program but the server has not been configured to > permit > SSL connections, an unencrypted connection is used. > > In a similar manner to the new '--ssl' option behaviour, users of the MySQL > client library (Connector/C, libmysqlclient), as of MySQL 5.7.3, can take > advantage of the MYSQL_OPT_SSL_ENFORCE option to enforce SSL/TLS > connections. > > The vulnerability also affects the MySQL forks MariaDB and Percona Server, > as > the relevant 5.7.3 patch has not been pulled, at the time of this > advisory, in > their respective stable versions. > > Affected version: > > MySQL <= 5.7.2 > > MySQl Connector/C (libmysqlclient) < 6.1.3 > > Percona Server, all versions > > MariaDB, all versions > > Fixed version: > > MySQL >= 5.7.3 > > MySQl Connector/C (libmysqlclient) >= 6.1.3 > > Percona Server, N/A > > MariaDB, N/A > > Credit: vulnerability report from Adam Goodman, Principal Security > Architect > at Duo Security. > > CVE: CVE-2015-3152 (MariaDB, Percona) > > Timeline: > > 2015-03-20: vulnerability report received > 2015-03-23: contacted Oracle Security > 2015-04-04: oCERT sets embargo date to April 29th > 2015-04-20: reporter confirms MariaDB is affected > 2015-04-22: contacted MariaDB and affected vendors, assigned CVEs > 2015-04-23: contacted Percona > 2015-04-29: advisory release > > References: > > https://github.com/mysql/mysql-server/commit/3bd5589e1a5a93f9c224badf983cd65c45215390 > http://mysqlblog.fivefarmers.com/2014/04/02/redefining-ssl-option > http://dev.mysql.com/doc/relnotes/mysql/5.7/en/news-5-7-3.html > https://mariadb.atlassian.net/browse/MDEV-7937 > https://bugs.launchpad.net/percona-server/+bug/1447527 > > Permalink: > http://www.ocert.org/advisories/ocert-2015-003.html > > -- > Andrea Barisani | Founder & Project Coordinator > oCERT | OSS Computer Security Incident Response Team > > <lcars@...rt.org> http://www.ocert.org > 0x864C9B9E 0A76 074A 02CD E989 CE7F AC3F DA47 578E 864C 9B9E > "Pluralitas non est ponenda sine necessitate" > -- Jon Oberheide <jon@...rheide.org> GnuPG Key: 4096R/52961381 Fingerprint: 964B 79EF 47D4 D7D0 CF73 D456 97FF B9D2 5296 1381
Powered by blists - more mailing lists
Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.
Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.