In computer security, arbitrary code execution is an attacker’s ability to execute arbitrary commands or code on a target machine or in a target process. An arbitrary code execution vulnerability is a security flaw in software or hardware allowing arbitrary code execution.
Multiple vulnerabilities have been discovered in Google Chrome, the most severe of which could allow for arbitrary code execution. Successful exploitation of the most severe of these vulnerabilities could allow an attacker to execute arbitrary code in the context of the browser. Depending on the privileges associated with the application, an attacker could view, change, or delete data. If this application has been configured to have fewer user rights on the system, exploitation of the most severe of these vulnerabilities could have less impact than if it was configured with administrative rights.
Google is aware of reports that an exploit for CVE-2021-21193 exists in the wild.
Affected Systems: Google Chrome versions prior to 89.0.4389.90
– Large and medium government entities: High
– Small government entities: Medium
– Large and medium business entities: High
– Small business entities: Medium
Home Users: Low
Multiple vulnerabilities have been discovered in Google Chrome, the most severe of which could allow for arbitrary code execution. These vulnerabilities can be exploited if a user visits, or is redirected to, a specially crafted web page. Details of the vulnerabilities are as follows:
- Use after free in WebRTC. (CVE-2021-21191)
- Heap buffer overflow in tab groups. (CVE-2021-21192)
- Use after free in Blink. (CVE-2021-21193)
We recommend the following actions be taken:
- Apply the stable channel update provided by Google to vulnerable systems immediately after appropriate testing.
- Run all software as a non-privileged user (one without administrative privileges) to diminish the effects of a successful attack.
- Remind users not to visit un-trusted websites or follow links provided by unknown or un-trusted sources.
- Inform and educate users regarding the threats posed by hypertext links contained in emails or attachments especially from un-trusted sources.
- Apply the Principle of Least Privilege to all systems and services.
How to Update Google Chrome:
- On your computer, open Chrome.
- At the top right, click More .
- Click Update Google Chrome. Important: If you can’t find this button, you’re on the latest version.
- Click Relaunch
The NJCCIC encourages recipients who discover signs of malicious cyber activity to contact the NJCCIC via the cyber incident report form at www.cyber.nj.gov/report.
Please do not hesitate to contact the NJCCIC at with any questions. Also, for more background on our recent cybersecurity efforts please visit cyber.nj.gov.