A use‑after‑free bug in Chrome’s PowerBookmarks feature allows an attacker who can compromise the renderer process to execute arbitrary code outside the browser sandbox. The flaw causes freed memory to be reused, giving the attacker control over execution flow once the object is accessed again. This can lead to complete system compromise, including privilege escalation on the user’s machine.

Google Chrome browsers on all platforms before version 157.0.8103.38 are affected. Users running any pre‑157.0.8103.38 build that has the PowerBookmarks feature enabled are at risk.

Chromium rates the issue as high severity. The EPSS score is not available, and the vulnerability is not listed in CISA KEV. The attack requires an attacker to first compromise the renderer process, which can happen through social engineering or a malicious extension. Once the renderer is compromised, the exploit immediately grants execution outside the sandbox, posing a substantial risk to users who install suspicious extensions or fall for phishing.