CVE-2017-18264: Debian Linux

Critical severity, CVSS 9.8. EPSS: 2.8% chance of exploitation in the next 30 days.

An issue was discovered in libraries/common.inc.php in phpMyAdmin 4.0 before 4.0.10.20, 4.4.x, 4.6.x, and 4.7.0 prereleases. The restrictions caused by $cfg['Servers'][$i]['AllowNoPassword'] = false are bypassed under certain PHP versions (e.g., version 5). This can allow the login of users who have no password set even if the administrator has set $cfg['Servers'][$i]['AllowNoPassword'] to false (which is also the default). This occurs because some implementations of the PHP substr function return false when given '' as the first argument.

Affected products

• Debian Debian Linux: version 8.0 only
• phpMyAdmin phpMyAdmin: from 4.0.0, before 4.0.10.20 (fixed in 4.0.10.20); from 4.4.0, up to and including 4.4.15.10; from 4.6.0, up to and including 4.6.6; version 4.7.0 only

Published 2018-05-01. Last modified 2026-06-17.