cbcvebase.
CVE-2021-39152
published 2021-08-23

CVE-2021-39152: XStream is a simple library to serialize objects to XML and back again. In affected versions this vulnerability may allow a remote attacker to request data…

PriorityP179high8.5CVSS 3.1
AVNACHPRLUINSCCHIHAH
ITWEXPLOITVulnCheck KEV
Exploited in the wild
EPSS
11.38%
95.5th 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 request data from internal resources that are not publicly available only by manipulating the processed input stream with a Java runtime version 14 to 8. No user is affected, who followed the recommendation to setup XStream's security framework with a whitelist limited to the minimal required types. If you rely on XStream's default blacklist of the [Security Framework](https://x-stream.github.io/security.html#framework), you will have to use at least version 1.4.18.

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

urlhttp://{{interactsh-url}}/internal/
sigma
matchers-condition: and
matchers:
- type: word
  part: interactsh_protocol
  words:
  - "http"

- type: word
  part: interactsh_request
  words:
  - "User-Agent: Java"
  • SSRF exploit payload targets jdk.nashorn.internal.runtime.Source$URLData via unsafe XStream deserialization; monitor for outbound HTTP requests with 'User-Agent: Java' originating from the application server after processing XML input.
  • The nuclei PoC probe payload uses GBK encoding and targets an internal URL path '/internal/' — look for XML deserialization requests containing internal URL references with GBK charset declarations.
  • Detection confirmation relies on an out-of-band HTTP callback with a Java User-Agent; deploy OOB interaction monitoring (e.g., interactsh/Burp Collaborator) and alert on Java-originating HTTP callbacks triggered by XML deserialization.
  • ·Users who configured XStream's security framework with a whitelist limited to the minimal required types are NOT affected by this vulnerability.
  • ·OpenShift Container Platform Jenkins package is not affected due to JEP-200 and JEP-228 protections already in place.
  • ·Vulnerability only affects Java runtime versions 8 through 14; environments outside this range are not impacted.

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
vulncheck8.5HIGH
vendor_debian8.5HIGH
vendor_redhat8.5HIGH
vendor_ubuntu8.5HIGH
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