Privilege escalation refers to a situation where an attacker or malicious actor uses an existing account or permissions and manages to increase the level of permission to perform unauthorized actions. This can be done in a number of ways, including exploiting vulnerabilities in the system or application, using stolen credentials, or manipulating user permissions.
For example, an attacker may be able to gain access to a system with limited privileges as a regular user, but then use a privilege escalation attack to gain administrative privileges and access to more sensitive resources. This can allow the attacker to make changes to the system, access sensitive data, or install malicious software.