Actively exploited in the wild
XStream Remote Code Execution Vulnerability
XStream - XStream · Listed in the CISA KEV since 2023-03-10. This indicates confirmed attacks in production environments.
Required action: Apply updates per vendor instructions.
CVE-2021-39144
HighCVSS 8.5KEVSummary
XStream is a simple library to serialize objects to XML and back again. In affected versions this vulnerability may allow a remote attacker with sufficient rights to execute commands of the 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. XStream 1.4.18 uses no longer a blacklist by default, since it cannot be secured for general purpose.
Risk Assessment
A remote attacker with sufficient rights can execute arbitrary commands on the server, potentially leading to full system compromise.
Recommendation
Update XStream to version 1.4.18 or later and configure the security framework with a whitelist of allowed types.
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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 has sufficient rights to execute commands of the 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. XStream 1.4.18 uses no longer a blacklist by default, since it cannot be secured for general purpose.