WordPress Plugin Email Subscribers & Newsletters 3.4.7

There is an information disclosure vulnerability in the WordPress plugin Email Subscribers & Newsletters <=3.4.7. This vulnerability is caused by the lack of authorization checks when using a core function of the plugin that lists all the subscribers’ information.

Exploitation

Stages

1. An unauthenticated attacker requests a WordPress server to run a plugin function that is vulnerable.
2. The function returns a list of information about subscribers, including emails and groups.

Prerequisites

The attack is unauthenticated and needs to be posted to an instance with the plugin installed. Additionally, the parameter ‘es’ must be in the URI but the parameter ‘option’ can be in either a post body or URI.

Alert Logic Coverage

Alert Logic® has evaluated its customer base for exposure to the exploit and has developed signatures for mitigating the threat depending on the security service in place.

The Network-Based Intrusion Detection System (IDS) has been updated with the new signatures for this exploit when detected via Alert Logic Threat Manager™. If this signature is detected, an incident is generated in the Alert Logic console.

Recommendations for Mitigation

To mitigate the vulnerability, upgrade to a non-vulnerable version of the plugin.