trestle-auth is an authentication plugin for the Trestle admin framework. A vulnerability in trestle-auth versions 0.4.0 and 0.4.1 allows an attacker to create a form that will bypass Rails' built-in CSRF protection when submitted by a victim with a trestle-auth admin session. This potentially allows an attacker to alter protected data, including admin account credentials. The vulnerability has been fixed in trestle-auth 0.4.2 released to RubyGems.