Google Releases Chrome Emergency Fix For Ninth Zero

CVE-2022-4135 is a heap buffer overflow (CWE-787, out-of-bounds write) in the GPU process of Google Chromium, the browser engine behind Chrome and most other major browsers. It is triggered via a crafted HTML page and, per CISA, requires the attacker to have already compromised the browser's renderer process; the memory corruption in the GPU process can then be leveraged to escape the renderer sandbox. A successful attack moves the attacker out of the tightly restricted renderer sandbox toward the higher-privilege GPU process on the host, a step that can enable further code execution. All users of Chromium-based browsers are affected — CISA explicitly lists Google Chrome, Microsoft Edge, and Opera, among others — though no specific vulnerable version ranges are published in the source data. Exploitation is confirmed in the wild: CISA added the flaw to the Known Exploited Vulnerabilities catalog on 2022-11-28, EPSS assigns a 31.9% probability of exploitation within 30 days (98th percentile), and no public proof-of-concept is known.

Do: Treat unpatched Chromium-based browsers as exposed and apply vendor updates immediately, per CISA's required action: update Google Chrome, Microsoft Edge, Opera, and any other Chromium-based browsers to the latest patched releases available as of the late-November 2022 KEV listing. Inventory managed endpoints for browser versions and verify auto-update is enabled, since the flaw is confirmed exploited in the wild even though no public PoC exists.

CVE-2022-4262 is a type confusion vulnerability in the V8 JavaScript engine used by Google Chrome, in which incorrect handling of object types can lead to heap corruption. An attacker can trigger the flaw by convincing a user to visit a specially crafted HTML page, with no privileges or special network access required. Successful exploitation could allow remote code execution or information disclosure within the browser process, and the High severity rating and web-reachable attack vector reflect significant potential impact. All Google Chrome users running versions prior to 108.0.5359.94 are affected, as are users of Chromium-based browsers incorporating the vulnerable V8 code. The vulnerability was a zero-day exploited in the wild prior to the patch — attributed by media reports to commercial spyware vendors targeting Android and iOS devices — and CISA added it to the Known Exploited Vulnerabilities catalog on 2022-12-05.

Do: Update Google Chrome to 108.0.5359.94 or later on all endpoints, and apply equivalent updates from vendors of Chromium-based browsers (e.g., Microsoft Edge, Brave, Opera) as they ship patched V8 builds. Verify the fixed version is running via chrome://settings/help or your patch-management inventory, and treat browser exploit chains as a spyware risk: review endpoint telemetry for signs of compromise, especially on mobile or high-target devices. CISA's required action is to apply updates per vendor instructions.