cbcvebase.
CVE-2021-21345
published 2021-03-23

CVE-2021-21345: XStream is a Java library to serialize objects to XML and back again. In XStream before version 1.4.16, there is a vulnerability which may allow a remote…

PriorityP182critical9.9CVSS 3.1
AVNACLPRLUINSCCHIHAH
EXPLOIT
EPSS
72.32%
99.4th percentile
XStream is a Java library to serialize objects to XML and back again. In XStream before version 1.4.16, there is a vulnerability which may allow a remote attacker who has sufficient rights to execute commands of the 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. If you rely on XStream's default blacklist of the Security Framework, you will have to use at least version 1.4.16.

Affected

41 ranges· showing 25
VendorProductVersion rangeFixed in
apacheactivemq< 5.15.145.15.14
apacheactivemq
apacheactivemq
apachejmeter< 5.55.5
debiandebian_linux
debiandebian_linux
debiandebian_linux
debianlibxstream-java< libxstream-java 1.4.15-2 (bookworm)libxstream-java 1.4.15-2 (bookworm)
fedoraprojectfedora
fedoraprojectfedora
fedoraprojectfedora
oraclebanking_enterprise_default_management
oraclebanking_enterprise_default_management
oraclebanking_platform
oraclebanking_platform
oraclebanking_platform
oraclebanking_platform
oraclebanking_virtual_account_management
oraclebanking_virtual_account_management
oraclebanking_virtual_account_management
oraclebusiness_activity_monitoring
oraclebusiness_activity_monitoring
oraclebusiness_activity_monitoring
oraclecommunications_billing_and_revenue_management_elastic_charging_engine
oraclecommunications_policy_management

Detection & IOCsextracted from sources · hover to see the quote

othercom.sun.corba.se.impl.activation.ServerTableEntry
sigma
matchers-condition: and
matchers:
- type: word
  part: interactsh_protocol
  words:
  - "http"

- type: word
  part: interactsh_request
  words:
  - "User-Agent: curl"
  • The exploit payload uses unsafe deserialization of the class com.sun.corba.se.impl.activation.ServerTableEntry within a crafted XStream XML input stream. Detect presence of this class name in deserialized XML input to XStream-consuming endpoints.
  • The PoC/nuclei template triggers an outbound HTTP request via curl to a callback URL; monitor for unexpected outbound curl User-Agent requests originating from Java application servers as a sign of successful RCE.
  • The exploit XML payload embeds the gadget class name com.sun.corba.se.impl.activation.ServerTableEntry; inspect HTTP request bodies and XML payloads for this string on endpoints that process XStream-deserialized data.
  • ·Users who configured XStream's security framework with a whitelist limited to the minimal required types are NOT affected. Only deployments relying on XStream's default blacklist are vulnerable.
  • ·OpenShift Container Platform Jenkins packages are NOT affected due to JEP-200 and JEP-228 protections applied to the bundled XStream library.
  • ·Red Hat JBoss AMQ 6 distributes affected XStream versions but is not susceptible because the XStream security framework with an allowlist is in place.

CVSS provenance

nvdv3.19.9CRITICALCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
nvdv2.06.5MEDIUMAV:N/AC:L/Au:S/C:P/I:P/A:P
ghsa9.9CRITICAL
osv9.9CRITICAL
vendor_oracle9.9MEDIUM
vendor_ubuntu8.0HIGH
vendor_debian5.8MEDIUM
vendor_redhat5.8MEDIUM
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