{"id":"CVE-2021-21347","revision":null,"records":[{"revision":"4854070f1e924ea68c06c7c78bff800d","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2021-21347","aliases":[],"title":"XStream is vulnerable to an Arbitrary Code Execution attack","description":"XStream is a Java library to serialize objects to XML and back again. In XStream before version 1.4.16, there is a vulnerability which may allow a remote attacker to load and execute arbitrary code from a remote host only by manipulating the processed input stream. No user is affected, who followed the recommendation to setup XStream's security framework with a whitelist limited to the minimal required types. 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