CVE-2020-7457: 
vSphere ESXi Hypervisor vulnerability analysis and mitigation

CVE-2020-7457 is a use-after-free vulnerability discovered in FreeBSD's IPV6_2292PKTOPTIONS socket option set handler. The vulnerability was identified in FreeBSD 12.1-STABLE before r359565, 12.1-RELEASE before p7, 11.4-STABLE before r362975, 11.4-RELEASE before p1, and 11.3-RELEASE before p11. The issue was discovered by Andy Nguyen and was disclosed on July 8, 2020 (FreeBSD Advisory).

The vulnerability stems from missing synchronization in the IPV6_2292PKTOPTIONS socket option set handler, which contained a race condition. This synchronization issue could allow a malicious application to modify memory after it has been freed. The vulnerability has been assigned a CVSS score of 7.8 (HIGH) with the vector CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H (NetApp Advisory).

The successful exploitation of this vulnerability could lead to privilege escalation through memory corruption. A malicious user application could trigger memory corruption, potentially resulting in arbitrary code execution as the root user (FreeBSD Advisory).

The vulnerability has been implemented as a module in the Metasploit Framework, supporting several FreeBSD versions including 9.1, 9.2, 9.3, 12.0, and 12.1. The module was tested on FreeBSD versions ranging from 9.1 to 9.3, and 12.0 to 12.1, demonstrating the vulnerability's broad impact across different versions (Rapid7 Blog).

The vulnerability was patched in various FreeBSD versions through security updates. Users are advised to upgrade their systems to supported FreeBSD stable or release/security branches dated after the correction date and perform a system reboot. The fixes were implemented in stable/12 (r359565), releng/12.1 (r363026), stable/11 (r362975), releng/11.4 (r363026), and releng/11.3 (r363026) (FreeBSD Advisory).