Google has accidentally leaked details about an unfixed issue in Chromium that keeps JavaScript running in the background even when the browser is closed, allowing remote code execution on the device.

The flaw was reported by security researcher Lyra Rebane and acknowledged as valid in December 2022, as per the thread on Chromium Issue Tracker.

An attacker could exploit the problem to create a malicious webpage with a Service Worker, such as a download task, that never terminates. Rebane says that this could allow an attacker to execute JavaScript code on the visitors’ devices.