libxstream-java: XStream is a Java library to serialize objects to XML and back again
CVE-2021-21342 is fixed in libxstream-java on 1 platform, first by libxstream-java 1.4.11.1-1~18.04.2, released March 22, 2021. It is not reported as exploited. Patch Radar priority: Routine.
XStream is a Java library to serialize objects to XML and back again. InXStream before version 1.4.16, there is a vulnerability where the processedstream at unmarshalling time contains type information to recreate theformerly written objects. XStream creates therefore new instances based onthese type information. An attacker can manipulate the processed inputstream and replace or inject objects, that result in a server-side forgeryrequest. No user is affected, who followed the recommendation to setupXStream's security framework with a whitelist limited to the minimalrequired types. If you rely on XStream's default blacklist of the SecurityFramework, you will have to use at least version 1.4.16.
Where it's fixed
| Product | Fixed in | Fix | Released |
|---|---|---|---|
| Linux | |||
| libxstream-java · Ubuntu 18.04.6 LTS (bionic) | 1.4.11.1-1~18.04.2 | libxstream-java 1.4.11.1-1~18.04.2 | Mar 22, 2021 |
| libxstream-java · Ubuntu 20.04 LTS (focal) | 1.4.11.1-1ubuntu0.2 | libxstream-java 1.4.11.1-1ubuntu0.2 | Mar 22, 2021 |
| libxstream-java · Ubuntu 24.10 (oracular) | 1.4.15-2 | libxstream-java 1.4.15-2 | Jan 16, 2026 |
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