# CVE-2021-39151: libxstream-java: XStream is a simple library to serialize objects to XML and back again

CVE-2021-39151 is fixed in libxstream-java on 1 platform, first by libxstream-java 1.4.11.1-1+deb10u4build0.18.04.1, released December 27, 2022. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-39151
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0474
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 23, 2021

## Description

XStream is a simple library to serialize objects to XML and back again. In affected versions this vulnerability may allow a remote attacker to load and execute arbitrary code from a remote 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. XStream 1.4.18 uses no longer a blacklist by default, since it cannot be secured for general purpose.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | libxstream-java Ubuntu 18.04.6 LTS (bionic) | 1.4.11.1-1+deb10u4build0.18.04.1 | [libxstream-java 1.4.11.1-1+deb10u4build0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libxstream-java-1.4.11.1-1-deb10u4build0.18.04.1.md) | Dec 27, 2022 |
| Linux | libxstream-java Ubuntu 20.04 LTS (focal) | 1.4.11.1-1ubuntu0.3 | [libxstream-java 1.4.11.1-1ubuntu0.3](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libxstream-java-1.4.11.1-1ubuntu0.3.md) | Dec 27, 2022 |

---

Data as of 2026-11-08T06:59:42Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.