# CVE-2021-39144: XStream is vulnerable to a Remote Command Execution attack

> CVE-2021-39144: XStream is vulnerable to a Remote Command Execution attack. CVSS 8.5 (CVSS 3.1), in CISA KEV.

Canonical: https://rewindex.com/cve/CVE-2021-39144
Last updated: 2025-10-21T23:25:37Z

- Published: 2021-08-23 00:00 UTC · Updated: 2025-10-21 23:25 UTC · Assigner: GitHub\_M
- CVSS: 8.5 (CVSS 3.1) · Severity: High · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
- EPSS: 98.1%, 100th percentile (scored 2026-10-25)
- CISA KEV: yes, added 2023-03-10, federal due date 2023-03-31, ransomware use: Unknown
- CWE: CWE-502, CWE-94

## Description

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

## CISA required action

Apply updates per vendor instructions.

## Affected vendors and products

- x-stream: xstream

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2021-39144)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2021-39144)
- [http://packetstormsecurity.com/files/169859/VMware-NSX-Manager-XStream-Unauthenticated-Remote-Code-Execution.html](http://packetstormsecurity.com/files/169859/VMware-NSX-Manager-XStream-Unauthenticated-Remote-Code-Execution.html)
- [https://github.com/x-stream/xstream/security/advisories/GHSA-j9h8-phrw-h4fh](https://github.com/x-stream/xstream/security/advisories/GHSA-j9h8-phrw-h4fh)
- [https://lists.debian.org/debian-lts-announce/2021/09/msg00017.html](https://lists.debian.org/debian-lts-announce/2021/09/msg00017.html)
- [https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/22KVR6B5IZP3BGQ3HPWIO2FWWCKT3DHP/](https://lists.fedoraproject.org/archives/list/package-announce%2540lists.fedoraproject.org/message/22KVR6B5IZP3BGQ3HPWIO2FWWCKT3DHP/)
- [https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PVPHZA7VW2RRSDCOIPP2W6O5ND254TU7/](https://lists.fedoraproject.org/archives/list/package-announce%2540lists.fedoraproject.org/message/PVPHZA7VW2RRSDCOIPP2W6O5ND254TU7/)
- [https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QGXIU3YDPG6OGTDHMBLAFN7BPBERXREB/](https://lists.fedoraproject.org/archives/list/package-announce%2540lists.fedoraproject.org/message/QGXIU3YDPG6OGTDHMBLAFN7BPBERXREB/)
- [https://security.netapp.com/advisory/ntap-20210923-0003/](https://security.netapp.com/advisory/ntap-20210923-0003/)
- [https://www.debian.org/security/2021/dsa-5004](https://www.debian.org/security/2021/dsa-5004)
- [https://www.oracle.com/security-alerts/cpuapr2022.html](https://www.oracle.com/security-alerts/cpuapr2022.html)
- [https://www.oracle.com/security-alerts/cpujan2022.html](https://www.oracle.com/security-alerts/cpujan2022.html)
- [https://www.oracle.com/security-alerts/cpujul2022.html](https://www.oracle.com/security-alerts/cpujul2022.html)
- [https://x-stream.github.io/CVE-2021-39144.html](https://x-stream.github.io/CVE-2021-39144.html)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2021-39144 · Markdown: https://rewindex.com/cve/CVE-2021-39144.md · JSON: https://rewindex.com/api/v1/cves/CVE-2021-39144 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:16:38.630Z