CVE-2026-12454 is a race condition vulnerability in the Safe Browsing feature of Google Chrome on Mac systems before version 149.0.7827.155. An attacker who has already compromised the renderer process could exploit this flaw by delivering a specially crafted HTML page to perform a sandbox escape, potentially leading to elevated privileges or code execution outside the browser sandbox. The vulnerability carries a CVSS 3.1 base score of 8.3, indicating high severity. The vendor has published an advisory linked to a stable channel update, implying that a fix is available in version 149.0.7827.155.

Successful exploitation could allow a remote attacker, who has compromised the renderer process, to escape the sandbox protection in Google Chrome on Mac. This could lead to execution of arbitrary code with higher privileges than normally allowed within the browser sandbox, compromising system security and user data confidentiality and integrity.

A fix is available in Google Chrome version 149.0.7827.155. Users and administrators should update affected Chrome installations on Mac to this version or later to remediate the vulnerability. Refer to the official Google Chrome stable channel update advisory at https://chromereleases.googleblog.com/2026/06/stable-channel-update-for-desktop_01750511403.html for update instructions and confirmation of the patch.