In horizontal privilege escalation, the attacker uses a normal account to access the accounts of other users. It is a simple process since the attacker does not actively seek to upgrade the privileges of an account, they are granted to him. Therefore, no tools are used to upgrade the accounts in this type of privilege escalation. There are two main ways through which a horizontal privilege escalation can occur. The first one is through software bugs, whereby a normal user is able to view and access files of other users due to an error in the coding of a system. As can be seen, no tools have been used and yet an attacker is able to access files that should have otherwise been protected from the eyes of normal users.

Another instance is that wherein the attacker is lucky to compromise an administrator's account. In this scenario, there will be no need to use hacking tools and techniques to escalate the privileges of the account that the user has hacked. Already adorned with the admin-level privileges, attackers can go on with the attack by creating other admin-level users or just use the already hacked account to execute the attack. Horizontal privilege escalation attacks are normally facilitated by tools and techniques that steal login credentials at the phase where hackers compromise a system. A number of tools were discussed in the chapter on compromising the system, where it was shown that a hacker can recover passwords, steal them from users, or crack directly into accounts. In fortunate scenarios for the hacker, the user accounts compromised will belong to users with high-level privileges. Therefore, they will not have to face any hardships of having to upgrade an account.