The package com.google.code.gson:gson before 2.8.9 are vulnerable to Deserialization of Untrusted Data via the writeReplace() method in internal classes, which may lead to DoS attacks.
The MITRE CVE dictionary describes this issue as:
The package com.google.code.gson:gson before 2.8.9 are vulnerable to Deserialization of Untrusted Data via the writeReplace() method in internal classes, which may lead to DoS attacks.
Vulmon