Input validation error in Ruby on Rails

1) Input validation error

EUVDB-ID: #VU31841

Risk: Medium

CVSSv4.0: 5.5 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/U:Green]

CVE-ID: CVE-2013-0156

CWE-ID: CWE-20 - Improper input validation

Exploit availability: Yes

Description

The vulnerability allows a remote non-authenticated attacker to read and manipulate data.

active_support/core_ext/hash/conversions.rb in Ruby on Rails before 2.3.15, 3.0.x before 3.0.19, 3.1.x before 3.1.10, and 3.2.x before 3.2.11 does not properly restrict casts of string values, which allows remote attackers to conduct object-injection attacks and execute arbitrary code, or cause a denial of service (memory and CPU consumption) involving nested XML entity references, by leveraging Action Pack support for (1) YAML type conversion or (2) Symbol type conversion.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Ruby on Rails: 3.1.0.beta1 - 3.1.9

CPE2.3

• cpe:2.3:a:rails:ruby_on_rails:3.1.0.beta1:*:*:*:*:*:*:*
• cpe:2.3:a:rails:ruby_on_rails:3.1.0:*:*:*:*:*:*:*
• cpe:2.3:a:rails:ruby_on_rails:3.1.0:rc1:*:*:*:*:*:*
• cpe:2.3:a:rails:ruby_on_rails:3.1.0:rc2:*:*:*:*:*:*
• cpe:2.3:a:rails:ruby_on_rails:3.1.0:rc3:*:*:*:*:*:*
• cpe:2.3:a:rails:ruby_on_rails:3.1.0:rc4:*:*:*:*:*:*
• cpe:2.3:a:rails:ruby_on_rails:3.1.0:rc5:*:*:*:*:*:*
• cpe:2.3:a:rails:ruby_on_rails:3.1.0:rc6:*:*:*:*:*:*
• cpe:2.3:a:rails:ruby_on_rails:3.1.0:rc7:*:*:*:*:*:*
• cpe:2.3:a:rails:ruby_on_rails:3.1.0:rc8:*:*:*:*:*:*

External links

https://ics-cert.us-cert.gov/advisories/ICSA-13-036-01A
https://lists.apple.com/archives/security-announce/2013/Mar/msg00002.html
https://rhn.redhat.com/errata/RHSA-2013-0153.html
https://rhn.redhat.com/errata/RHSA-2013-0154.html
https://rhn.redhat.com/errata/RHSA-2013-0155.html
https://weblog.rubyonrails.org/2013/1/28/Rails-3-0-20-and-2-3-16-have-been-released/
https://www.debian.org/security/2013/dsa-2604
https://www.fujitsu.com/global/support/software/security/products-f/sw-sv-rcve-ror201301e.html
https://www.insinuator.net/2013/01/rails-yaml/
https://www.kb.cert.org/vuls/id/380039
https://www.kb.cert.org/vuls/id/628463
https://community.rapid7.com/community/metasploit/blog/2013/01/09/serialization-mischief-in-ruby-land-cve-2013-0156
https://groups.google.com/group/rubyonrails-security/msg/c1432d0f8c70e89d?dmode=source&output=gplain
https://puppet.com/security/cve/cve-2013-0156

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.