CVE-2026-0889 is a denial-of-service vulnerability affecting the DOM Service Workers component in Mozilla Firefox. The flaw allows an attacker to disrupt service availability by exploiting the Service Workers implementation in the browser. This vulnerability was addressed and fixed in Firefox 147. The CVSS v3.1 base score is 7.5, indicating a high severity level primarily due to its network attack vector and lack of required privileges or user interaction. The vendor advisory confirms the fix and provides no indication of active exploitation.

The vulnerability can cause denial of service, impacting the availability of Firefox when processing Service Workers. There is no indication of confidentiality or integrity impact. No known exploits in the wild have been reported. The impact is limited to service disruption rather than code execution or data compromise.

An official fix is available and was released in Firefox 147. Users and administrators should update affected Firefox installations to version 147 or later to remediate this vulnerability. No additional mitigation steps are required as the issue is resolved by the update.