This vulnerability (CVE-2025-11152) is an integer overflow in the Canvas2D graphics component of Mozilla Firefox that enables sandbox escape. The sandbox is a critical security boundary isolating web content from the underlying system. An integer overflow here can lead to memory corruption or other unsafe conditions that attackers might leverage to execute code outside the sandbox. Mozilla addressed this issue in Firefox 143.0.3, as documented in their security advisory MFSA2025-80.

Successful exploitation of this vulnerability could allow an attacker to escape the Firefox sandbox, potentially leading to arbitrary code execution with the privileges of the user running the browser. The CVSS vector indicates network attack vector, low attack complexity, no privileges or user interaction required, with impacts on confidentiality (low), integrity (high), and availability (low). This makes it a high-impact vulnerability if exploited.

Mozilla has released an official fix for this vulnerability in Firefox version 143.0.3. Users and administrators should update to this version or later to remediate the issue. Since this is a client-side application vulnerability, patching the browser is the primary mitigation. There are no vendor advisories indicating that no action is required or that the issue is already mitigated without patching.