cbcvebase.
CVE-2021-21349
published 2021-03-23

CVE-2021-21349: 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…

PriorityP267high8.6CVSS 3.1
AVNACLPRNUINSCCHINAN
EPSS
46.83%
98.7th 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 to request data from internal resources that are not publicly available 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

43 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

  • CVE-2021-21349 is an SSRF vulnerability triggered during XStream XML deserialization (unmarshalling). Detect suspicious XML payloads containing URL-referencing constructs (e.g., java.net.URL or sun.net.www types) passed to XStream's fromXML() or similar entry points.
  • Monitor outbound HTTP/HTTPS/FTP connections originating from the JVM process handling XStream deserialization, particularly to internal/intranet IP ranges (RFC-1918) or localhost (127.0.0.1), as these indicate successful SSRF exploitation.
  • Applications using XStream versions prior to 1.4.16 without a whitelist-based security framework are vulnerable. Identify and flag any deployment of XStream < 1.4.16 in your environment.
  • If relying on XStream's default blacklist (rather than a whitelist), the application remains exploitable. Audit XStream security framework configuration to confirm whitelist enforcement is in place.
  • ·Users who configured XStream's security framework with a whitelist limited to the minimal required types are NOT affected by this vulnerability, regardless of XStream version.
  • ·OpenShift Container Platform Jenkins packages are NOT affected due to JEP-200 and JEP-228 protections applied to the bundled XStream library.
  • ·Debian resolved this CVE in package version 1.4.15-2 (not 1.4.16 upstream), meaning the Debian fix is a backport — version string alone may not be a reliable indicator on Debian-based systems.

CVSS provenance

nvdv3.18.6HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:P/I:N/A:N
ghsa8.6HIGH
osv8.8HIGH
vendor_ubuntu8.0HIGH
vendor_debian6.1MEDIUM
vendor_redhat6.1MEDIUM
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