AdminNeo is a full-featured database management tool written in PHP. From 4.6.2 until 5.5.0, the unauthenticated `?script=version` endpoint accepts POST data without origin, CSRF or parameter-type validation. A `version[]` parameter becomes a PHP array that `bootstrap.inc.php` serializes into the shared `adminneo.version` cache.
On later page loads, `design.inc.php` passes that cached value to `cookie()` and `rawurlencode()`, causing a `TypeError` rather than encoding a version string. A remote attacker can make the instance return HTTP 500 to all users for the cache's twenty-four-hour lifetime or until the poisoned cache is removed. Exploitation requires the web server to be able to write that shared cache; making it unwritable is an interim workaround.
The issue retains the underlying type-validation defect reported previously in Adminer despite changes to AdminNeo's version-checking flow. This issue is fixed in version 5.5.0.
Attack Parameters
Impact Assessment
CVSS Vector v3.1