CVE Catalog

CVE-2021-39139

HighCVSS 8.5
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Very high risk
4.54%

91th percentile - higher than 91% of all known CVEs

Summary

XStream is a library for serializing objects to XML and back. The vulnerability allows a remote attacker to execute arbitrary code from a remote host 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, but the scenario can be adjusted to an external Xalan that works regardless of Java runtime version. Users who configured the security framework with a whitelist are not affected. Version 1.4.18 no longer uses a blacklist by default.

Risk Assessment

The risk for the organization is remote code execution, especially in environments with outdated JDK versions. The attack can be performed remotely without authentication if the application processes untrusted XML data.

Recommendation

It is recommended to upgrade XStream to version 1.4.18 or later and upgrade JDK to a newer version. Configure the security framework with a whitelist of types.

Other vulnerabilities in XStream

See all
Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS