The Chrome Updater on macOS validates untrusted input poorly, enabling a local attacker to replace or inject update files that are executed with Chrome’s privileges. This flaw permits an attacker who can place a malicious file in the updater directory to run code with the same rights as the user running Chrome, effectively achieving OS‑level privilege escalation. The weakness is a classic improper input validation bug, classified as CWE‑20. The official Chromium severity for this issue is Low, but the impact of successfully exploiting the flaw is the full compromise of the affected machine.

Google Chrome versions on macOS older than 148.0.7778.96 are affected. The vulnerability resides in the updater component that accepts files from the local filesystem without adequate validation, allowing any user with write access to the updater folder to introduce and execute malicious updates.

The CVSS score of 7.8 indicates a high severity level. The vulnerability requires local access to place a malicious file in the Chrome Updater location. No publicly known exploit is available and the EPSS score is not provided. The vulnerability is not listed in the CISA KEV catalog. Therefore, while the potential impact of exploitation is high—giving the attacker system‑wide control—the risk of compromise is confined to environments where a local attacker can write to the updater directory. The official Chromium severity of Low reflects that the flaw is non‑remote but still potentially catastrophic if the local conditions are met.