XStream is a simple library to serialize objects to XML and back again. In affected versions this vulnerability may allow a remote attacker to load and execute arbitrary code from a remote host only by manipulating the processed input stream. A user is only affected if using the version out of the box with JDK 1.7u21 or below. However, this scenario can be adjusted easily to an external Xalan that works regardless of the version of the Java runtime. No user is affected, who followed the recommendation to setup XStream's security framework with a whitelist limited to the minimal required types. XStream 1.4.18 uses no longer a blacklist by default, since it cannot be secured for general purpose.
History

Wed, 07 Oct 2026 21:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Fri, 23 May 2025 17:15:00 +0000

Type Values Removed Values Added
First Time appeared Xstream
Xstream xstream
CPEs cpe:2.3:a:xstream_project:xstream:*:*:*:*:*:*:*:* cpe:2.3:a:xstream:xstream:*:*:*:*:*:*:*:*
Vendors & Products Xstream Project
Xstream Project xstream
Xstream
Xstream xstream

cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2021-08-23T17:50:14.000Z

Updated: 2026-10-07T19:58:53.438Z

Reserved: 2021-08-16T00:00:00.000Z

Link: CVE-2021-39139

cve-icon Vulnrichment

Updated: 2024-08-04T01:58:18.173Z

cve-icon NVD

Status : Analyzed

Published: 2021-08-23T18:15:10.540

Modified: 2026-10-07T21:17:03.330

Link: CVE-2021-39139

cve-icon Redhat

Severity : Important

Publid Date: 2021-08-22T00:00:00Z

Links: CVE-2021-39139 - Bugzilla