This vulnerability arises from insufficient validation of untrusted input in the Dawn component of Google Chrome on macOS versions before 149.0.7827.103. An attacker who has already compromised the renderer process can exploit this flaw to leak cross-origin data by delivering a specially crafted HTML page. The issue is recognized as high severity by the Chromium security team. No CVSS score is assigned, and no direct patch or remediation level is stated in the provided data. The vendor advisory URL points to a Chrome stable channel update that likely addresses this issue.

The impact of this vulnerability is the potential leakage of cross-origin data by an attacker who has compromised the renderer process. This could lead to unauthorized disclosure of sensitive information across origins within the browser context. There are no reports of active exploitation in the wild at this time.

The vendor advisory linked corresponds to a stable channel update for Chrome, indicating that a fix is available in version 149.0.7827.103 or later. Users should update Google Chrome on macOS to version 149.0.7827.103 or newer to remediate this vulnerability. Patch status is not explicitly confirmed in the input but can be verified by reviewing the vendor advisory at https://chromereleases.googleblog.com/2026/06/stable-channel-update-for-desktop_0153744567.html.