CVE Tools

CVE-2021-21345

XStream is vulnerable to a Remote Command Execution attack

Published: Mar 22, 2021Updated: May 23, 2025 Sources: CVE List NVD GHSA BDUCWE-94
5.8CVSSMEDIUM

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 which may allow a remote attacker who 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. 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:LUI:RS:CC:NI:HA:N
Exploitability
AV:NAttack Vector
Network
AC:HAttack Complexity
High
PR:LPrivileges Required
Low
UI:RUser Interaction
Required
Scope
S:CScope
Changed
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 50 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available
Workaround Available

MITRE ATT&CK

3 techniques
Execution
Initial Access
View detailed technique mapping

References

and 39 more references View all →

Timeline

Published
Mar 22, 2021
Last Updated
May 23, 2025

Unlock Complete Vulnerability Intelligence

Get the full picture for CVE-2021-21345 and every CVE in our database. Create a free account — no credit card required.

Create Free Account
Plain-language analysis
Impact assessment and exploitation scenario in plain English
Attack graph visualization
Interactive attack path and kill chain mapping
Exploit details & PoC links
ExploitDB, Metasploit, GitHub PoCs with direct links
Nuclei scanner templates
Ready-to-use vulnerability scanner templates
Full remediation guide
Patch instructions, workarounds, and compliance impact
Interactive AI chat
Ask questions about this vulnerability in natural language
Related vulnerabilities
Semantically similar CVEs and attack patterns
REST API & MCP access
Integrate vulnerability data into your workflows