An issue was discovered in phpMyAdmin involving the $cfg['ArbitraryServerRegexp'] configuration directive. An attacker could reuse certain cookie values in a way of bypassing the servers defined by ArbitraryServerRegexp. All 4.6.x versions (prior to 4.6.4), 4.4.x versions (prior to 4.4.15.8), and 4.0.x versions (prior to 4.0.10.17) are affected.