cbcvebase.
CVE-2021-29505
published 2021-05-28

CVE-2021-29505: XStream is software for serializing Java objects to XML and back again. A vulnerability in XStream versions prior to 1.4.17 may allow a remote attacker has…

PriorityP181high8.8CVSS 3.1
AVNACLPRLUINSUCHIHAH
EXPLOIT
EPSS
77.73%
99.5th percentile
XStream is software for serializing Java objects to XML and back again. A vulnerability in XStream versions prior to 1.4.17 may allow a remote attacker has sufficient rights to execute commands of the host only by manipulating the processed input stream. No user who followed the recommendation to setup XStream's security framework with a whitelist limited to the minimal required types is affected. The vulnerability is patched in version 1.4.17.

Affected

42 ranges· showing 25
VendorProductVersion rangeFixed in
debiandebian_linux
debiandebian_linux
debiandebian_linux
debianlibxstream-java< libxstream-java 1.4.15-3 (bookworm)libxstream-java 1.4.15-3 (bookworm)
fedoraprojectfedora
fedoraprojectfedora
fedoraprojectfedora
oraclebanking_cash_management
oraclebanking_cash_management
oraclebanking_cash_management
oraclebanking_corporate_lending_process_management
oraclebanking_corporate_lending_process_management
oraclebanking_corporate_lending_process_management
oraclebanking_credit_facilities_process_management
oraclebanking_credit_facilities_process_management
oraclebanking_credit_facilities_process_management
oraclebanking_supply_chain_finance
oraclebanking_trade_finance_process_management
oraclebusiness_activity_monitoring
oraclebusiness_activity_monitoring
oraclebusiness_activity_monitoring
oraclecommunications_brm_elastic_charging_engine
oraclecommunications_brm_elastic_charging_engine
oraclecommunications_unified_inventory_management
oraclecommunications_unified_inventory_management

Detection & IOCsextracted from sources · hover to see the quote

othercom.sun.xml.internal.ws.api.message.Packet
otherUnicastRef
port1099
sigma
matchers-condition: and
matchers:
- type: word
  part: interactsh_protocol
  words:
  - "dns"

- type: word
  part: body
  words:
  - "timestamp"
  - "com.thoughtworks.xstream"
  condition: or

- type: word
  part: header
  words:
  - "application/json"

- type: status
  status:
  - 500
  • Exploit payload uses a SOAP_11 envelope containing a com.sun.xml.internal.ws.api.message.Packet object with an embedded UnicastRef element pointing to an attacker-controlled RMI host on port 1099 — detect XML deserialization requests containing these class references.
  • Exploit triggers an outbound DNS callback to an interactsh/OOB interaction server; monitor for unexpected DNS lookups originating from Java application servers processing XStream-deserialized XML.
  • A successful exploit attempt against a vulnerable endpoint returns HTTP 500 with 'com.thoughtworks.xstream' in the response body and Content-Type application/json — use these as detection signals.
  • Deny-list regex for XStream 1.4.16 to block RMI-based exploitation: block types matching '(?:java|sun)\.rmi\..*' in the deserialization pipeline.
  • ·Only users who did NOT configure XStream's security framework with a whitelist of minimal required types are affected; whitelisted deployments are not vulnerable.
  • ·OpenShift Container Platform Jenkins packages are not affected due to JEP-200 and JEP-228 protections already in place.
  • ·CodeReady Studio 12 includes an affected XStream version as a transitive dependency for the Wise framework plugin, but the vulnerable code path is not invoked — rated Low severity for that product.

CVSS provenance

nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvdv2.06.5MEDIUMAV:N/AC:L/Au:S/C:P/I:P/A:P
ghsa8.8HIGH
osv8.8HIGH
vendor_oracle8.8HIGH
vendor_debian7.5HIGH
vendor_redhat7.5HIGH
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