Active Model in Ruby on Rails 4.1.x before 4.1.14.1, 4.2.x before 4.2.5.1, and 5.x before 5.0.0.beta1.1 supports the use of instance-level writers for class accessors, which allows remote attackers to bypass intended validation steps via crafted parameters.
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lists.opensuse.org/opensuse-security-announce/2016-04/msg00053.html
lists.opensuse.org/opensuse-updates/2016-02/msg00043.html
rhn.redhat.com/errata/RHSA-2016-0296.html
www.debian.org/security/2016/dsa-3464
www.openwall.com/lists/oss-security/2016/01/25/14
www.securityfocus.com/bid/82247
www.securitytracker.com/id/1034816
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