CVEs / CVE-2020-26217
CVE-2020-26217: x-stream xstream vulnerability
- high 8.8 CVSS 3.1 (NVD)
- EPSS 84.9% chance of exploitation in the next 30 days, higher than 99% of CVEs (5 Nov 2026)
- Last changed at its sources
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Description
XStream before version 1.4.14 is vulnerable to Remote Code Execution.The vulnerability may allow a remote attacker to run arbitrary shell commands only by manipulating the processed input stream. Only users who rely on blocklists are affected. Anyone using XStream's Security Framework allowlist is not affected. The linked advisory provides code workarounds for users who cannot upgrade. The issue is fixed in version 1.4.14.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| x-stream xstream | < 1.4.14 | — |
| Product | Affected | Fixed in |
|---|---|---|
| com.thoughtworks.xstream:xstream (Maven) | before 1.4.14-java7 | 1.4.14-java7 |
Package versions from GHSA-mw36-7c6c-q4q2.
Exploitation
Not in the CISA Known Exploited Vulnerabilities catalog as of 4 Nov 2026.
Severity
| CVSS 3.1 | 8.8 highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HScored by NVD |
|---|---|
| Weakness | CWE-78 |
References
- CVE-2020-26217 on NVD
- CVE-2020-26217 on OSV
- https://github.com/x-stream/xstream/commit/0fec095d534126931c99fd38e9c6d41f5c685c1a Patch, Third Party Advisory
- https://github.com/x-stream/xstream/security/advisories/GHSA-mw36-7c6c-q4q2 Mitigation, Third Party Advisory
- https://lists.apache.org/thread.html/r2de526726e7f4db4a7cb91b7355070779f51a84fd985c6529c2f4e9e%40%3Cissues.activemq.apache.org%3E Issue Tracking, Mailing List
- https://lists.apache.org/thread.html/r7c9fc255edc0b9cd9567093d131f6d33fde4c662aaf912460ef630e9%40%3Ccommits.camel.apache.org%3E Issue Tracking, Mailing List
- https://lists.apache.org/thread.html/r826a006fda71cc96fc87b6eca4b5d195f19a292ad36cea501682c38c%40%3Cissues.activemq.apache.org%3E Issue Tracking, Mailing List
- https://lists.apache.org/thread.html/redde3609b89b2a4ff18b536a06ef9a77deb93d47fda8ed28086fa8c3%40%3Cissues.activemq.apache.org%3E Issue Tracking, Mailing List
- https://lists.debian.org/debian-lts-announce/2020/12/msg00001.html Mailing List, Third Party Advisory
- https://security.netapp.com/advisory/ntap-20210409-0004/ Third Party Advisory
- https://www.debian.org/security/2020/dsa-4811 Third Party Advisory
- https://www.oracle.com//security-alerts/cpujul2021.html Patch, Third Party Advisory
- https://www.oracle.com/security-alerts/cpuApr2021.html Patch, Third Party Advisory
- https://www.oracle.com/security-alerts/cpuapr2022.html Not Applicable, Third Party Advisory
- https://www.oracle.com/security-alerts/cpujan2022.html Not Applicable, Third Party Advisory
- https://www.oracle.com/security-alerts/cpuoct2021.html Patch, Third Party Advisory
- https://x-stream.github.io/CVE-2020-26217.html Exploit, Mitigation, Vendor Advisory
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.