`CVE-2020-26217` XStream

Affected software	XStream
Severity	8.8 High CVSS 3.1 3 scores
Fixed in	`1.4.14-java7`
Weakness	OS command injection (CWE-78)
Published	16 Nov 2020
Updated	13 Nov 2026

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.

Exploitation status

Working exploit published

A reviewed exploit catalogue lists ready-to-run exploit code for this CVE.

CISA KEV not listed
VulnCheck KEV not listed
CISA Vulnrichment exploitation: none
Indexed PoC 4 indexed Published artifacts you can open, in GitHub PoC, Nuclei; first seen 2020-12-08.
EPSS 85% chance in 30 days A model's forecast, not a report of exploitation. Higher than 99.7% of all scored CVEs.

3 of these are GitHub repositories with fewer than 5 stars. They are listed for reference and don't count toward the exploitation status above.

Index	Artifact	Stars	First seen
GitHub PoC	CVE-2020-26217 XStream RCE POC	4	2020-12-08
GitHub PoC	CVE-2020-26217 && XStream RCE	3	2021-01-22
GitHub PoC	xstream with CVE-2020-26217		2024-05-31
Nuclei	XStream <1.4.14 - Remote Code Execution

Index

Artifact

Stars

First seen

GitHub PoC

CVE-2020-26217 XStream RCE POC

2020-12-08

GitHub PoC

CVE-2020-26217 && XStream RCE

2021-01-22

GitHub PoC

xstream with CVE-2020-26217

2024-05-31

Nuclei

XStream <1.4.14 - Remote Code Execution

Waratek protection

Protected by Waratek

Waratek has a rule that blocks attacks on this vulnerability.

Protection full Process
Action available security rule
Review human Researcher
Record active

Decided by	A researcher's recorded decision for this specific CVE
Finding	A researcher found this CVE protected by the ARMR Process PROTECT rule.

Decided by

A researcher's recorded decision for this specific CVE

Finding

A researcher found this CVE protected by the ARMR Process PROTECT rule.

Waratek research note

written 2026-11-13

Written by a Waratek engineer who reviewed this CVE. Their decision sets the status above, ahead of every automated rule except a withdrawal.

Comments

Rule Name: ARMR Process PROTECT rule

How to mitigate CVE-2020-26217

Upgrade XStream to 1.4.14-java7 or later. Until you can, Waratek RASP blocks exploitation with its process rule. It runs inside the Java application, with no code changes.

Waratek RASP Runtime protection for Java applications

CVSS

8.8 HIGH v3.1 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H 3 metrics

We show the highest score from the newest CVSS version. Scores from different versions can't be compared, and the first score listed is sometimes a 0.0 placeholder.

Version Score Band Vector Assigner Type

CVSS 3.1 8.8 HIGH CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H NVD Primary published

CVSS 3.1 8.0 HIGH CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:H security-advisories@github.com Secondary

CVSS 2.0 9.3 none AV:N/AC:M/Au:N/C:C/I:C/A:C NVD Primary

Version	Score	Band	Vector	Assigner	Type
CVSS 3.1	8.8	HIGH	`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`	NVD	Primary	published
CVSS 3.1	8.0	HIGH	`CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:H`	security-advisories@github.com	Secondary
CVSS 2.0	9.3	none	`AV:N/AC:M/Au:N/C:C/I:C/A:C`	NVD	Primary

Affected software and releases

Oracle advisories

Advisory	Type	Quarter	Products Oracle names in its risk matrix
Oracle Critical Patch Update April 2021 ↗	CPU	2021-Q2	Oracle Financial Services Applications / Collections (XStream) (2.4.0, 2.7.1, 2.9.0) Oracle Fusion Middleware / General (XStream) (11.1.1.9.0, 12.2.1.3.0, 12.2.1.4.0) Oracle Fusion Middleware / Studio (XStream) (3.2.0.0)

Advisory

Type

Quarter

Products Oracle names in its risk matrix

Oracle Critical Patch Update April 2021 ↗

CPU

2021-Q2

Oracle Financial Services Applications / Collections (XStream) (2.4.0, 2.7.1, 2.9.0)
Oracle Fusion Middleware / General (XStream) (11.1.1.9.0, 12.2.1.3.0, 12.2.1.4.0)
Oracle Fusion Middleware / Studio (XStream) (3.2.0.0)

Oracle components and versions

Family	Component	Versions, as Oracle lists them	Read as
Oracle Financial Services Applications	Collections (XStream)	2.4.0, 2.7.1, 2.9.0	2.4.0 · 2.7.1 · 2.9.0
Oracle Fusion Middleware	General (XStream)	11.1.1.9.0, 12.2.1.3.0, 12.2.1.4.0	11.1.1.9.0 · 12.2.1.3.0 · 12.2.1.4.0
Oracle Fusion Middleware	Studio (XStream)	3.2.0.0	3.2.0.0

Family

Component

Versions, as Oracle lists them

Read as

Oracle Financial Services Applications

Collections (XStream)

2.4.0, 2.7.1, 2.9.0

2.4.0 · 2.7.1 · 2.9.0

Oracle Fusion Middleware

General (XStream)

11.1.1.9.0, 12.2.1.3.0, 12.2.1.4.0

11.1.1.9.0 · 12.2.1.3.0 · 12.2.1.4.0

Oracle Fusion Middleware

Studio (XStream)

3.2.0.0

Maven packages

Affected and fixed versions, from OSV.dev

Package Introduced Fixed Last affected

com.thoughtworks.xstream:xstream 0 1.4.14-java7 unbounded

Package	Introduced	Fixed	Last affected
`com.thoughtworks.xstream:xstream`	0	`1.4.14-java7`	unbounded

Products and versions

16 products, 37 version entries

Source	Vendor	Product	Scheme	Affected versions
nvd	apache	activemq	generic	＜ 5.15.14 · 5.16.0
osv	com.thoughtworks.xstream	xstream	generic	＜ 1.4.14.7
nvd	debian	debian linux	generic	9.0 · 10.0
nvd	netapp	snapmanager	generic	any version
nvd	oracle	banking cash management	generic	14.2 · 14.3 · 14.5
nvd	oracle	banking corporate lending process management	generic	14.2 · 14.3 · 14.5
nvd	oracle	banking credit facilities process management	generic	14.2 · 14.3 · 14.5
nvd	oracle	banking platform	generic	2.4.0 · 2.7.1 · 2.9.0
nvd	oracle	banking supply chain finance	generic	14.2 · 14.3 · 14.5
nvd	oracle	banking trade finance process management	generic	14.2 · 14.3 · 14.5
nvd	oracle	banking virtual account management	generic	14.2.0 · 14.3.0 · 14.5.0
nvd	oracle	business activity monitoring	generic	11.1.1.9.0 · 12.2.1.3.0 · 12.2.1.4.0
nvd	oracle	communications policy management	generic	12.5.0
nvd	oracle	endeca information discovery studio	generic	3.2.0.0
nvd	oracle	retail xstore point of service	generic	16.0.6 · 17.0.4 · 18.0.3 · 19.0.2
nvd	xstream	xstream	generic	＜ 1.4.14

Source

Vendor

Product

Scheme

Affected versions

nvd

apache

activemq

generic

＜ 5.15.14 · 5.16.0

osv

com.thoughtworks.xstream

xstream

generic

＜ 1.4.14.7

nvd

debian

debian linux

generic

9.0 · 10.0

nvd

netapp

snapmanager

generic

any version

nvd

oracle

banking cash management

generic

14.2 · 14.3 · 14.5

nvd

oracle

banking corporate lending process management

generic

14.2 · 14.3 · 14.5

nvd

oracle

banking credit facilities process management

generic

14.2 · 14.3 · 14.5

nvd

oracle

banking platform

generic

2.4.0 · 2.7.1 · 2.9.0

nvd

oracle

banking supply chain finance

generic

14.2 · 14.3 · 14.5

nvd

oracle

banking trade finance process management

generic

14.2 · 14.3 · 14.5

nvd

oracle

banking virtual account management

generic

14.2.0 · 14.3.0 · 14.5.0

nvd

oracle

business activity monitoring

generic

11.1.1.9.0 · 12.2.1.3.0 · 12.2.1.4.0

nvd

oracle

communications policy management

generic

12.5.0

nvd

oracle

endeca information discovery studio

generic

3.2.0.0

nvd

oracle

retail xstore point of service

generic

16.0.6 · 17.0.4 · 18.0.3 · 19.0.2

nvd

xstream

generic

＜ 1.4.14

Earlier manual review

A reviewer classified this CVE in an older dataset. We kept the labels and products below, but not the reviewer's reasoning.

## Manual Classification Context **Labels:** HTTP, COLLECTIONS (XSTREAM), GENERAL (XSTREAM), STUDIO (XSTREAM) **Products:** ORACLE BAM (BUSINESS ACTIVITY MONITORING), ORACLE BANKING PLATFORM, XSTREAM, ORACLE ENDECA INFORMATION DISCOVERY STUDIO, ORACLE FUSION MIDDLEWARE, ORACLE FINANCIAL SERVICES APPLICATIONS

References

URL	Tags
https://github.com/x-stream/xstream/security/advisories/GHSA-mw36-7c6c-q4q2	WEB
https://github.com/x-stream/xstream/commit/0fec095d534126931c99fd38e9c6d41f5c685c1a	WEB
https://x-stream.github.io/CVE-2020-26217.html	WEB
https://www.oracle.com/security-alerts/cpuoct2021.html	WEB
https://www.oracle.com/security-alerts/cpujan2022.html	WEB
https://www.oracle.com/security-alerts/cpuapr2022.html	WEB
https://www.oracle.com/security-alerts/cpuApr2021.html	WEB
https://www.oracle.com//security-alerts/cpujul2021.html	WEB
https://www.debian.org/security/2020/dsa-4811	WEB
https://security.netapp.com/advisory/ntap-20210409-0004	WEB

URL

Timeline

Published	2020-11-16	By the CVE Program.
NVD record modified	2026-10-07	NVD's own last-modified date for this record.
Classification created	2026-11-13	First commit adding this CVE's research note.
Last VRT activity	2026-11-13	Most recent commit touching this CVE's classification, patch or rule file.

Published

2020-11-16

By the CVE Program.

NVD record modified

2026-10-07

NVD's own last-modified date for this record.

Classification created

2026-11-13

First commit adding this CVE's research note.

Last VRT activity

2026-11-13

Most recent commit touching this CVE's classification, patch or rule file.

How VRT decided (4 of 24 rules ran)

4 of 24 rules ran. The rest didn't run because an earlier rule had already settled the CVE.

# Rule Outcome Status Detail

identity: Does this identifier describe a vulnerability at all? the first rule that matches decides

1 rejected no match CVE Program withdrawal of this identifier

scope: Is it a vulnerability Waratek protects? the first rule that matches decides

2 armr-patch-file no match An ARMR patch file on disk for this CVE

3 armr-secure-rule-file no match An ARMR security-rule template on disk for this CVE

4 manual-classification decided it matched Protected by Waratek A researcher found this CVE protected by the ARMR Process PROTECT rule.

5 manual classification not reached Manual classification of this CVE in the legacy dataset

6 non-java-upstream not reached A root cause in non-Java code: an OS kernel, a C library, or a bundled runtime

7 oracle-component not reached The defect being in a component of a tracked product the agent does not reach: JavaFX, the Java SE installer, the JInitiator browser plug-in, the native WebLogic proxy plug-in, or a native part of Oracle Application Server or Collaboration Suite (HTTP Server, Web Cache, Internet Directory, mail and calendar servers). Oracle gives these no CPE of their own and names them only in the description.

8 java-client-side not reached Oracle's own risk-matrix note saying the CVE is reached only through untrusted code in the Java sandbox (applets, Web Start) or only through a client installation of Java, so a server running its own trusted code is not exposed

9 osv-maven not reached An OSV.dev record of this CVE affecting a package published to Maven Central. When every such package is one business applications do not use (Minecraft mods and launchers, Fastjson) and no tracked product is named by CPE, it settles the CVE as Outside Waratek scope instead

10 cna-maven-package not reached An affected Maven artifact named by the CNA itself

11 known-cpe-product not reached An NVD CPE naming a product ARMR tracks

12 cna-cpe-product not reached A CPE the CNA published naming a tracked product. Oracle publishes these on advisory day, months before NVD.

13 oracle-advisory-family not reached A tracked product family named in Oracle's own risk matrix. CPE cannot carry a suite name, only a module.

14 cna-named-product not reached A tracked product named in words by the CVE's own CNA, on a record with no CPE yet. Apache and Eclipse publish these on advisory day, before NVD adds CPE data.

15 non-deployable-product not reached The only affected product being a sealed appliance image, where Java runs but no -javaagent can be attached

16 unmatched-product not reached No tracked product matched above, and none present at all

disposition: What do we do about one that is? every rule runs

17 patch-hint not reached A reference pointing at the upstream fix: a commit, a PR, a Red Hat bug

18 open-source-maven not reached The affected package being open source on Maven, so the fix can be read

19 poc-derivable not reached An indexed exploit clearing the evidence bar to reverse-engineer, where there is no source to read

20 no-exploit not reached Nothing to build a rule from yet: no published exploit, no CISA record of exploitation and no source-level change to read

21 secure-rule-match not reached A vulnerability class already blocked by an ARMR security rule

22 exploited-no-fix-or-poc not reached Somebody exploiting this CVE (a CISA or VulnCheck KEV listing, or a CISA verdict of active exploitation), with no fix, source code or PoC to build a rule from

23 below-action-threshold not reached Medium or Low severity, no CISA or VulnCheck KEV listing, no PoC clearing the evidence bar, no CISA verdict, no Oracle advisory

24 no-exploit-published not reached Exploit code for this candidate, published in a reviewed catalogue or a GitHub repository with 5 or more stars, or in use per CISA or VulnCheck; not only a CISA verdict, a forecast, or nothing at all

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