High (7.5). EPSS 2.0% chance of exploitation in the next 30 days. Fixed in com.thoughtworks.xstream:xstream 1.4.21.
XStream is a simple library to serialize objects to XML and back again. This vulnerability may allow a remote attacker to terminate the application with a stack overflow error resulting in a denial of service only by manipulating the processed input stream when XStream is configured to use the BinaryStreamDriver. XStream 1.4.21 has been patched to detect the manipulation in the binary input stream causing the the stack overflow and raises an InputManipulationException instead. Users are advised to upgrade. Users unable to upgrade may catch the StackOverflowError in the client code calling XStream if XStream is configured to use the BinaryStreamDriver.
Severity
CVSS 3.1
7.5 high
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
2.0% chance of exploitation in the next 30 days; higher than 80% of CVEs (scores of 2026-10-31)