The MITRE CVE dictionary describes this issue as:
Vulnerability in the Java SE, JRockit component of Oracle Java SE (subcomponent: Serialization). Supported versions that are affected are Java SE: 6u171 and 7u161; JRockit: R28.3.16. Easily exploitable vulnerability allows unauthenticated attacker with network access via multiple protocols to compromise Java SE, JRockit. Successful attacks of this vulnerability can result in unauthorized ability to cause a partial denial of service (partial DOS) of Java SE, JRockit. Note: This vulnerability can only be exploited by supplying data to APIs in the specified Component without using Untrusted Java Web Start applications or Untrusted Java applets, such as through a web service. CVSS 3.0 Base Score 5.3 (Availability impacts). CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L).
Find out more about CVE-2018-2657 from the
MITRE CVE dictionary dictionary and