An incorrect authorization check (CWE-863) in Chrome’s CustomTabs component permits a local attacker to bypass the web origin policy. A co‑installed malicious application can launch a CustomTab and access web content or data from origins that should remain isolated. Based on the description, it is inferred that this could enable disclosure or manipulation of sensitive information, though the exact extent depends on the malicious app’s capabilities.

Google Chrome for Android versions prior to 152.0.7977.65. The issue is limited to Android devices that use the CustomTabs interface to launch web content.

The flaw requires a local attacker with the ability to install a co‑existing app that can register itself as a CustomTabs provider. With the EPSS score of <1% and the vulnerability not listed in CISA’s KEV catalog, malicious exploitation is currently unproven. The high CVSS score of 9.8 indicates a critical risk, yet the Chromium security severity is Low, suggesting that the potential for widespread impact is limited. Nonetheless, any user who installs or allows a suspicious app to register a CustomTabs service could be affected.