Description

In the referenced code, known uses an insecure RNG to generate a password because, in its words; this should "mitigate security holes if cleanup fails" - unfortunately, if the cleanup fails - an attacker may be able to predict the password to the created account.

Proof of Concept

See the php documentation for rand() that highlights its insecure nature.

Impact

This vulnerability is capable of providing an attacker with access to a test account.