CVE-2021-39148 | XStream is vulnerable to an Arbitrary Code Execution attack

Exp

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.

Published: 2021-08-23 Last update: 2025-05-23 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-39148 is rated High Exploit Risk (74/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.67%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2021-39148

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2021-39148

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-03-10 0.57% 0.67% +0.10%
2 2025-12-28 0.48% 0.57% +0.09%
3 2025-12-27 0.48%

Full EPSS history (34 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-39148

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.5 3.1 HIGH
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.8 6.0 [email protected]
8.5 3.1 HIGH
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.8 6.0 [email protected]
6.0 2.0 MEDIUM
AV:N/AC:M/Au:S/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
6.8 6.4 [email protected]

Weakness enumeration for CVE-2021-39148

GitHub Security Advisory for CVE-2021-39148

GHSA-qrx8-8545-4wg2 · Severity: high · Ecosystem: maven — XStream is vulnerable to an Arbitrary Code Execution attack

OS Trackers for CVE-2021-39148

vendor priority summary link
debian not yet assigned CVE-2021-39148 not yet assigned priority: Debian including 1 source packages (libxstream-java), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2021-39148
redhat high https://access.redhat.com/security/cve/CVE-2021-39148
suse high CVE-2021-39148 severity important: SUSE including 12 source package names (5.0.0-beta1.2.122:xstream-1.4.18-3.14.1, 5.1.0.6.40:xstream-1.4.18-3.14.1, …), 47 product×package rows across 31 product lines (Container suse/manager/5.0/x86_64/server, Container suse/multi-linux-manager/5.1/x86_64/server, … (31 product lines)): Fixed 47. https://www.suse.com/security/cve/CVE-2021-39148/
ubuntu medium CVE-2021-39148 medium priority: Ubuntu including 1 source packages (libxstream-java), 10 status rows across 10 suites (bionic, focal, hirsute, impish, jammy, kinetic, lunar, trusty, upstream, xenial): not-affected 5, ignored 2, released 2, needs-triage 1. https://ubuntu.com/security/CVE-2021-39148

Affected software / configurations for CVE-2021-39148

Vendor Product Version Raw CPE
xstream xstream < 1.4.18 cpe:2.3:a:xstream:xstream:*:*:*:*:*:*:*:*
fedoraproject fedora 33 cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
fedoraproject fedora 34 cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
fedoraproject fedora 35 cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
debian debian_linux 9.0 cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
debian debian_linux 10.0 cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
debian debian_linux 11.0 cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*
netapp snapmanager cpe:2.3:a:netapp:snapmanager:-:*:*:*:*:oracle:*:*
netapp snapmanager cpe:2.3:a:netapp:snapmanager:-:*:*:*:*:sap:*:*
oracle business_activity_monitoring 12.2.1.4.0 cpe:2.3:a:oracle:business_activity_monitoring:12.2.1.4.0:*:*:*:*:*:*:*
oracle commerce_guided_search 11.3.2 cpe:2.3:a:oracle:commerce_guided_search:11.3.2:*:*:*:*:*:*:*
oracle communications_billing_and_revenue_management_elastic_charging_engine 11.3 cpe:2.3:a:oracle:communications_billing_and_revenue_management_elastic_charging_engine:11.3:*:*:*:*:*:*:*
oracle communications_billing_and_revenue_management_elastic_charging_engine 12.0 cpe:2.3:a:oracle:communications_billing_and_revenue_management_elastic_charging_engine:12.0:*:*:*:*:*:*:*
oracle communications_cloud_native_core_automated_test_suite 1.9.0 cpe:2.3:a:oracle:communications_cloud_native_core_automated_test_suite:1.9.0:*:*:*:*:*:*:*
oracle communications_cloud_native_core_binding_support_function 1.10.0 cpe:2.3:a:oracle:communications_cloud_native_core_binding_support_function:1.10.0:*:*:*:*:*:*:*
oracle communications_cloud_native_core_policy 1.14.0 cpe:2.3:a:oracle:communications_cloud_native_core_policy:1.14.0:*:*:*:*:*:*:*
oracle communications_unified_inventory_management 7.3.4 cpe:2.3:a:oracle:communications_unified_inventory_management:7.3.4:*:*:*:*:*:*:*
oracle communications_unified_inventory_management 7.3.5 cpe:2.3:a:oracle:communications_unified_inventory_management:7.3.5:*:*:*:*:*:*:*
oracle communications_unified_inventory_management 7.4.0 cpe:2.3:a:oracle:communications_unified_inventory_management:7.4.0:*:*:*:*:*:*:*
oracle communications_unified_inventory_management 7.4.1 cpe:2.3:a:oracle:communications_unified_inventory_management:7.4.1:*:*:*:*:*:*:*
oracle communications_unified_inventory_management 7.4.2 cpe:2.3:a:oracle:communications_unified_inventory_management:7.4.2:*:*:*:*:*:*:*
oracle retail_xstore_point_of_service 16.0.6 cpe:2.3:a:oracle:retail_xstore_point_of_service:16.0.6:*:*:*:*:*:*:*
oracle retail_xstore_point_of_service 17.0.4 cpe:2.3:a:oracle:retail_xstore_point_of_service:17.0.4:*:*:*:*:*:*:*
oracle retail_xstore_point_of_service 18.0.3 cpe:2.3:a:oracle:retail_xstore_point_of_service:18.0.3:*:*:*:*:*:*:*
oracle retail_xstore_point_of_service 19.0.2 cpe:2.3:a:oracle:retail_xstore_point_of_service:19.0.2:*:*:*:*:*:*:*
oracle retail_xstore_point_of_service 20.0.1 cpe:2.3:a:oracle:retail_xstore_point_of_service:20.0.1:*:*:*:*:*:*:*
oracle utilities_framework 4.2.0.2.0 cpe:2.3:a:oracle:utilities_framework:4.2.0.2.0:*:*:*:*:*:*:*
oracle utilities_framework 4.2.0.3.0 cpe:2.3:a:oracle:utilities_framework:4.2.0.3.0:*:*:*:*:*:*:*
oracle utilities_framework 4.3.0.1.0 cpe:2.3:a:oracle:utilities_framework:4.3.0.1.0:*:*:*:*:*:*:*
oracle utilities_framework 4.3.0.6.0 cpe:2.3:a:oracle:utilities_framework:4.3.0.6.0:*:*:*:*:*:*:*
oracle utilities_framework 4.4.0.0.0 cpe:2.3:a:oracle:utilities_framework:4.4.0.0.0:*:*:*:*:*:*:*
oracle utilities_framework 4.4.0.2.0 cpe:2.3:a:oracle:utilities_framework:4.4.0.2.0:*:*:*:*:*:*:*
oracle utilities_framework 4.4.0.3.0 cpe:2.3:a:oracle:utilities_framework:4.4.0.3.0:*:*:*:*:*:*:*
oracle utilities_testing_accelerator 6.0.0.1.1 cpe:2.3:a:oracle:utilities_testing_accelerator:6.0.0.1.1:*:*:*:*:*:*:*
oracle webcenter_portal 12.2.1.3.0 cpe:2.3:a:oracle:webcenter_portal:12.2.1.3.0:*:*:*:*:*:*:*
oracle webcenter_portal 12.2.1.4.0 cpe:2.3:a:oracle:webcenter_portal:12.2.1.4.0:*:*:*:*:*:*:*

References for CVE-2021-39148

URL Tags
https://github.com/x-stream/xstream/security/advisories/GHSA-qrx8-8545-4wg2 Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/09/msg00017.html Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/22KVR6B5IZP3BGQ3HPWIO2FWWCKT3DHP/ Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PVPHZA7VW2RRSDCOIPP2W6O5ND254TU7/ Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QGXIU3YDPG6OGTDHMBLAFN7BPBERXREB/ Mailing List
https://security.netapp.com/advisory/ntap-20210923-0003/ Third Party Advisory
https://www.debian.org/security/2021/dsa-5004 Third Party Advisory
https://www.oracle.com/security-alerts/cpuapr2022.html Patch Third Party Advisory
https://www.oracle.com/security-alerts/cpujan2022.html Patch Third Party Advisory
https://www.oracle.com/security-alerts/cpujul2022.html Third Party Advisory
https://x-stream.github.io/CVE-2021-39148.html Exploit Third Party Advisory
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