CVE-2021-39147

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. 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

8.5CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H

EPSS

4.7% chance of exploitation in the next 30 days; higher than 91% of CVEs (scores of 2026-10-25)

CWEs

CWE-434, CWE-502

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)

References

• https://github.com/x-stream/xstream/security/advisories/GHSA-h7v4-7xg3-hxcc
• https://lists.debian.org/debian-lts-announce/2021/09/msg00017.html
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/22KVR6B5IZP3BGQ3HPWIO2FWWCKT3DHP/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PVPHZA7VW2RRSDCOIPP2W6O5ND254TU7/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QGXIU3YDPG6OGTDHMBLAFN7BPBERXREB/

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