The vulnerability stems from incorrect authorization handling in Chrome's Accessibility subsystem. An attacker who has already compromised the renderer process can craft a malicious HTML page that bypasses the browser's site isolation boundary, potentially exposing sensitive information from other sites. The weakness is classified as CWE-863 and carries a high severity rating.

Google Chrome browsers running any version prior to 155.0.8059.39 are affected. No additional version details are provided by the CNA.

The CVSS score of 8.1 indicates high severity, and the vulnerability is not listed in the CISA KEV catalog, meaning no known public exploitation. The EPSS score is < 1%, indicating a very low but nonzero probability of exploitation. The attack requires a prior compromise of the renderer process, which could be achieved via malicious web content or compromised extensions.