CVE Tools

CVE-2021-21342

A Server-Side Forgery Request can be activated unmarshalling with XStream to access data streams from an arbitrary URL referencing a resource in an intranet or the local host

Published: Mar 22, 2021Updated: May 23, 2025 Sources: CVE List NVD GHSA BDUCWE-502
5.3CVSSMEDIUM

Description

XStream is a Java library to serialize objects to XML and back again. In XStream before version 1.4.16, there is a vulnerability where the processed stream at unmarshalling time contains type information to recreate the formerly written objects. XStream creates therefore new instances based on these type information. An attacker can manipulate the processed input stream and replace or inject objects, that result in a server-side forgery request. No user is affected, who followed the recommendation to setup XStream's security framework with a whitelist limited to the minimal required types. If you rely on XStream's default blacklist of the Security Framework, you will have to use at least version 1.4.16.

CVSS Vector Breakdown

AV:NAC:HPR:NUI:RS:UC:NI:HA:N
Exploitability
AV:NAttack Vector
Network
AC:HAttack Complexity
High
PR:NPrivileges Required
None
UI:RUser Interaction
Required
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:HIntegrity
High
A:NAvailability
None

Weaknesses

Affected Products

x-streamoss-projectOSS Librariesaka xstream
mavenpackage-ecosystemOSS Libraries
apacheoss-projectUSWeb & CMS Pluginsaka apache http server, apache httpd
and 44 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

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Exploitability

1 exploit source identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available
Workaround Available

MITRE ATT&CK

4 techniques
Command and Control
Execution
Initial Access
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References

and 38 more references View all →

Timeline

Published
Mar 22, 2021
Last Updated
May 23, 2025

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