Issue #9424 has been updated by Yusuke Endoh.


Charlie Somerville wrote:
> Several members of the community have already offered to assist in maintaining more secure defaults in the OpenSSL extension.

Please give us not only words but also a concrete plan.  

The following is just my personal opinion, not the consensus of ruby-core.  This issue must be eventually determined by Matz and Martin Bosslet who is the maintainer of Ruby OpenSSL.



The matter is how we determine what is "secure".
I believe that the (current) Ruby committers are not qualified to determine that.  We are more or less experts for the Ruby implementation, but not for crypto.  In an extreme case, default settings chosen by ignoramus are not only invalid but also harmful.  Providing such a thing is really unfaithful.
It is possibly dangerous to trust a bug reporter blindly.  At least we must validate their reports.  But we might get tricked.


I thought that the best person to determine that was the OpenSSL project itself.  However, according to some people, OpenSSL seems not to be interested in secure defaults.  That's unfortunate, but I respect their decision.


Then, I think of three possibilities:

* To follow the same policy as OpenSSL, i.e., delegating the task to users.
* To replace Ruby OpenSSL with another implementations, such as krypt.
* To find another authority to follow.

I think the third is best, but we must determine the following things.

* The authority that suggests a good configuration.  NIST?  NESSIE?  CRYPTREC?  Or what?  I'm not sure.
* A trusted, motivated, and expert committer(s) who can interpret and implement the suggested configuration into Ruby OpenSSL.
* Preparation to continue following the changes of the configuration.

-- 
Yusuke Endoh <mame / tsg.ne.jp>

----------------------------------------
Bug #9424: ruby 1.9 & 2.x has insecure SSL/TLS client defaults 
https://bugs.ruby-lang.org/issues/9424#change-44502

* Author: Jeff Hodges
* Status: Assigned
* Priority: Normal
* Assignee: Martin Bosslet
* Category: ext/openssl
* Target version: current: 2.2.0
* ruby -v: ruby 2.1.0p0 (2013-12-25 revision 44422) [x86_64-darwin12]
* Backport: 1.9.3: UNKNOWN, 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
Ruby 1.9, 2.0, and 2.1 use insecure defaults for SSL/TLS client connections. They have inherited or overridden configs that make the OpenSSL-controlled connections insecure. Note: both OpenSSL's and Ruby's defaults in all tested versions are currently insecure. Confirmation of the issues with Ruby's TLS client can be done with the code in [1].

Ruby is using TLS compression by default. This opens Ruby clients to the CRIME attack[2].

Ruby also uses a variety of insecure cipher suites. These cipher suites either use key sizes much smaller than the currently recommended size, making brute forcing a decryption easy, or do not check the veracity of the server's certificate making them susceptible to man-in-the-middle attacks[3][4].

Ruby also appears to allow SSLv2 connections by default. It does so by first trying to connect with a SSLv2 client hello with a higher SSL/TLS version inside of it which allows SSLv2 servers to work. SSLv2 was broken in the 1990s and is considered unsafe.

These issues expose Ruby users to attacks that have been known for many years, and are trivial to discover. These defaults are often build specific, and are not the same across platforms, but are consistently poor (the code in [1] can evaluate the build). A patch from a core developer on the security@ list is attached. However, the patch does not correct the suspect SSLv2 configuration. It is believed that Ruby 1.8 is also a concern, but, since it was obsoleted, it's not been investigated.

A report similar to this was sent to security / ruby-lang.org four days ago. The Ruby core developers have been unable to patch these problems in a timely manner for it for what I and others believe are concerning reasons. This ticket is being made to allow engineers outside of the small group that are on security@ to protect themselves from these attacks.

[1] https://gist.github.com/cscotta/8302049
[2] https://www.howsmyssl.com/s/about.html#tls-compression
[3] https://www.howsmyssl.com/s/about.html#insecure-cipher-suites
[4] TLS_DHE_DSS_WITH_DES_CBC_SHA - small keys
TLS_DHE_RSA_WITH_DES_CBC_SHA - small keys
TLS_ECDH_anon_WITH_3DES_EDE_CBC_SHA - MITM
TLS_ECDH_anon_WITH_AES_128_CBC_SHA - MITM
TLS_ECDH_anon_WITH_AES_256_CBC_SHA - MITM
TLS_ECDH_anon_WITH_RC4_128_SHA - MITM
TLS_RSA_WITH_DES_CBC_SHA - small keys
TLS_SRP_SHA_WITH_3DES_EDE_CBC_SHA - MITM
TLS_SRP_SHA_WITH_AES_128_CBC_SHA - MITM
TLS_SRP_SHA_WITH_AES_256_CBC_SHA - MITM

---Files--------------------------------
ruby_ssl.patch (1.08 KB)


-- 
http://bugs.ruby-lang.org/