CVE-2026-16369 describes an integer overflow vulnerability in the JavaScript: WebAssembly component of Mozilla Firefox. This vulnerability allows an attacker to cause memory corruption or other unintended behavior due to improper handling of integer values. The issue was addressed and fixed in Firefox 153 and Firefox ESR 140.13. The CVSS v3.1 base score is 9.8, indicating critical severity with network attack vector, no privileges required, no user interaction, and impacts to confidentiality, integrity, and availability. The vendor advisory confirms the fix and notes no known exploitation in the wild.

Successful exploitation of this integer overflow vulnerability could lead to arbitrary code execution or other severe impacts compromising the browser's security properties, including confidentiality, integrity, and availability. The CVSS score of 9.8 reflects the critical nature of this vulnerability. However, no active exploitation has been observed in the wild as per the vendor advisory.

Mozilla has released official fixes for this vulnerability in Firefox 153 and Firefox ESR 140.13. Users and administrators should update affected Firefox versions to these or later versions to remediate the vulnerability. Since this is not a cloud service, patching the client software is required. There is no indication from the vendor advisory that any other mitigation or workaround is necessary.