CVE-2026-7686 | eyeo Adblock Plus up to 4.36.2 on Chrome Legacy Premium Activation premium.preload.js postMessage access control

A vulnerability was found in eyeo Adblock Plus up to 4.36.2 on Chrome. It has been classified as problematic. Affected by this vulnerability is the function postMessage of the file premium.preload.js of the component Legacy Premium Activation. Performing a manipulation results in improper access controls.

This vulnerability is known as CVE-2026-7686. Remote exploitation of the attack is possible. Furthermore, an exploit is available.

Upgrading the affected component is recommended.

The vendor provides additional details: “The affected code path is a legacy Premium activation flow that has been deprecated. eyeo has already migrated to a new user account-based licensing system. The exploit does not grant permanent Premium access. The licensing server issues a short-lived trial license (valid for approximately 24 hours) for any submitted userId. On the next license check, the server validates against a real subscription and the trial expires if no valid subscription is found. The researcher’s claim of permanently unlocking all Premium features is therefore incorrect. (…) The old flow has been present for years and has not been weaponized at scale to our knowledge. The risk to eyeo and to users is minimal.”VulDB Recent EntriesRead More