cbcvebase.
CVE-2021-39141
published 2021-08-23

CVE-2021-39141: 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…

PriorityP270high8.5CVSS 3.1
AVNACHPRLUINSCCHIHAH
EXPLOIT
EPSS
16.12%
96.6th percentile
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.

Affected

36 ranges· showing 25
VendorProductVersion rangeFixed in
debiandebian_linux
debiandebian_linux
debiandebian_linux
debianlibxstream-java< libxstream-java 1.4.18-1 (bookworm)libxstream-java 1.4.18-1 (bookworm)
fedoraprojectfedora
fedoraprojectfedora
fedoraprojectfedora
oraclebusiness_activity_monitoring
oraclecommerce_guided_search
oraclecommunications_billing_and_revenue_management_elastic_charging_engine
oraclecommunications_billing_and_revenue_management_elastic_charging_engine
oraclecommunications_cloud_native_core_automated_test_suite
oraclecommunications_cloud_native_core_binding_support_function
oraclecommunications_cloud_native_core_policy
oraclecommunications_unified_inventory_management
oraclecommunications_unified_inventory_management
oraclecommunications_unified_inventory_management
oraclecommunications_unified_inventory_management
oraclecommunications_unified_inventory_management
oracleretail_xstore_point_of_service
oracleretail_xstore_point_of_service
oracleretail_xstore_point_of_service
oracleretail_xstore_point_of_service
oracleretail_xstore_point_of_service
oracleutilities_framework

Detection & IOCsextracted from sources · hover to see the quote

urlldap://{{interactsh-url}}/#evil
  • Monitor for outbound LDAP connections triggered by the application server after processing XML input — a successful exploit causes the server to perform an LDAP lookup to an attacker-controlled host.
  • HTTP 500 response combined with 'com.thoughtworks.xstream' in the response body and 'application/json' Content-Type header is a strong indicator of a triggered XStream deserialization exploit attempt.
  • The exploit abuses unsafe deserialization of com.sun.xml.internal.ws.client.sei.* classes; alert on XStream XML payloads referencing these class paths.
  • DNS callback observed from the target host after processing a crafted XML payload confirms successful JNDI trigger; correlate with interactsh/OOB DNS hits.
  • ·Users who configured XStream's security framework with a whitelist limited to the minimal required types are NOT affected by this vulnerability.
  • ·XStream 1.4.18 removed the blacklist as the default security mechanism because it cannot be secured for general-purpose use; detections targeting blacklist bypass patterns may not apply to 1.4.18+.

CVSS provenance

nvdv3.18.5HIGHCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
nvdv2.06.0MEDIUMAV:N/AC:M/Au:S/C:P/I:P/A:P
ghsa8.5HIGH
osv8.8HIGH
vendor_debian8.5HIGH
vendor_redhat8.5HIGH
vendor_ubuntu8.5HIGH
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