An information disclosure vulnerability exists when DirectWrite improperly discloses the contents of its memory. An attacker who successfully exploited the vulnerability could obtain information to further compromise the user’s system. There are multiple ways an attacker could exploit the vulnerability, such as by convincing a user to open a specially crafted document, or by convincing a user to visit an untrusted webpage. The security update addresses the vulnerability by correcting how DirectWrite handles objects in memory.
https://www.tenable.com/blog/microsoft-s-august-2020-patch-tuesday-addresses-120-cves-cve-2020-1337
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1577