CVE-2020-16009

CVE-2020-16009 is a type confusion vulnerability (CWE-843) in the V8 JavaScript engine used by Google Chromium, which can lead to heap corruption (CWE-787). A remote attacker triggers it by getting a user to load a specially crafted HTML page, such as via a malicious or compromised website. Successful exploitation corrupts the heap and can potentially allow the attacker to execute code in the context of the affected browser. Any Chromium-based browser or application embedding V8 is affected, including Google Chrome, Microsoft Edge, and Opera, meaning the affected population is effectively the entire Chromium user base worldwide. CISA added the flaw to its Known Exploited Vulnerabilities catalog on 2021-11-03, confirming exploitation in the wild, with an EPSS probability of 48.3% (99th percentile); ransomware use is unknown and no public PoC is known.

What to do: Apply the vendor update per CISA's required action: update all Chromium-based browsers (Chrome, Edge, Opera, and derivatives) to the latest stable releases from each vendor and restart browsers afterward. Inventory any embedded or packaged Chromium/V8 runtimes in other applications and update them as their maintainers ship fixes. Given confirmed in-the-wild exploitation and high EPSS, prioritize patching endpoints used for web browsing by high-risk users first.