Out-of-bounds read vulnerabilities allow attackers to read portions of the server's memory.
Attackers can read or write out-of-bounds heap data, resulting in application crashes or arbitrary remote code execution (RCE). Detailed tracking can be reviewed on the GitHub Advisory for CVE-2019-9023 . 2. XML-RPC Out-of-Bounds Read (CVE-2019-9020) php version 5640 vulnerabilities link