### [CVE-2021-4203](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-4203) ![](https://img.shields.io/static/v1?label=Product&message=kernel&color=blue) ![](https://img.shields.io/static/v1?label=Version&message=kernel%205.15%20rc4%20&color=brightgreen) ![](https://img.shields.io/static/v1?label=Vulnerability&message=CWE-362-%3ECWE-416&color=brightgreen) ### Description A use-after-free read flaw was found in sock_getsockopt() in net/core/sock.c due to SO_PEERCRED and SO_PEERGROUPS race with listen() (and connect()) in the Linux kernel. In this flaw, an attacker with a user privileges may crash the system or leak internal kernel information. ### POC #### Reference - https://www.oracle.com/security-alerts/cpujul2022.html #### Github - https://github.com/ARPSyndicate/cvemon - https://github.com/sam8k/Dynamic-and-Static-Analysis-of-SOUPs