CVE-2021-39140

6.3 mediumEPSS 5.9%

XStream is a simple library to serialize objects to XML and back again. In affected versions this vulnerability may allow a remote attacker to allocate 100% CPU time on the target system depending on CPU type or parallel execution of such a payload resulting in a denial of service 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.

CVSS 3.1: 6.3CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:N/A:H
EPSS: 5.9% chance of exploitation in the next 30 days; higher than 93% of CVEs (scores of 2026-10-25)
CWEs: CWE-502, CWE-835
Published: 2021-08-23
Modified: 2026-10-07
Record from: the NVD, synced 2026-10-19

Affected

debian:debian_linux
fedoraproject:fedora
netapp:snapmanager
oracle:business_activity_monitoring
oracle:commerce_guided_search
oracle:communications_billing_and_revenue_management_elastic_charging_engine
oracle:communications_cloud_native_core_automated_test_suite
oracle:communications_cloud_native_core_binding_support_function
oracle:communications_cloud_native_core_policy
oracle:communications_unified_inventory_management
oracle:retail_xstore_point_of_service
oracle:utilities_framework
oracle:utilities_testing_accelerator
oracle:webcenter_portal
xstream:xstream

Packages (OSV)

Advisory	Ecosystem	Package	Affected	Fixed in
GHSA-6wf9-jmg9-vxcc	Maven	com.thoughtworks.xstream:xstream	<1.4.18	1.4.18

References

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