The CVE-2021-21227 vulnerability is an insufficient data validation issue that could be exploited by remote attackers to achieve code execution within the target’s browser.
The vulnerability was reported to Google by Gengming Liu from the Chinese cybersecurity firm Singular Security Lab who also received a $15,000 award for this vulnerability.
The vulnerability could not be exploited by attackers to escape the Chrome sandbox, but chaining it with a sandbox escape exploit could allow the execution of malicious code on the underlying OS.
The CVE-2021-21227 flaw is linked to the CVE-2020-16040 and CVE-2020-15965 vulnerabilities that were addressed by Google in 2020. Chrome in December and September 2020, respectively.
Google has patched several serious V8 vulnerabilities in recent weeks, including some for which PoC exploits were released before patches were made available. For some of these security holes, Google warned that exploits exist in the wild.
The Chrome 90 update addressed a toatal of 9 vulnerabilities, including the CVE-2021-21227. Below the issues that were reported by external researchers:
- [$NA] High CVE-2021-21232: Use after free in Dev Tools. Reported by Abdulrahman Alqabandi, Microsoft Browser Vulnerability Research on 2021-02-05
- [$TBD] High CVE-2021-21233: Heap buffer overflow in ANGLE. Reported by Omair on 2021-02-26
- [$5000] Medium CVE-2021-21228: Insufficient policy enforcement in extensions. Reported by Rob Wu on 2020-10-16
- [$TBD] Medium CVE-2021-21229: Incorrect security UI in downloads. Reported by Mohit Raj (shadow2639) on 2021-04-12
- [$TBD] Medium CVE-2021-21230: Type Confusion in V8. Reported by Manfred Paul on 2021-04-13
- [$NA] Low CVE-2021-21231: Insufficient data validation in V8. Reported by Sergei Glazunov of Google Project Zero on 2021-04-13
[출처 : SecurityAffairs / 4.28.]