CVE-2020-10143: 
Homebrew vulnerability analysis and mitigation

CVE-2020-10143 is a privilege escalation vulnerability discovered in Macrium Reflect software. The vulnerability was introduced in the Macrium Reflect 7.2 series and was publicly disclosed on October 26, 2020. The issue affects systems with vulnerable Macrium software installed (CERT VU).

The vulnerability exists due to Macrium Reflect's OpenSSL component specifying an OPENSSLDIR variable as C:\openssl. Since unprivileged Windows users can create subdirectories off of the system root, an attacker can create the appropriate path to a specially-crafted openssl.cnf file to achieve arbitrary code execution with SYSTEM privileges (CERT VU).

When successfully exploited, this vulnerability allows an unprivileged user to execute arbitrary code with SYSTEM privileges on a Windows system with the vulnerable Macrium software installed (CERT VU).

The vulnerability can be exploited by placing a specially-crafted openssl.cnf file in the C:\openssl\ directory, which can be created by any unprivileged user on the Windows system (CERT VU).

The vulnerability has been patched in Macrium Reflect v7.3.5281. All users of affected releases are entitled to a free upgrade to version 7.3.5281 or later (CERT VU).

Macrium acknowledged the vulnerability and credited Will Dormann (@wdormann) for reporting the issue to them (CERT VU).