CVE-2021-39144

XStream Remote Code Execution Vulnerability

n/a

CVSS

98.1%

EPSS (exploit prob.)

99.9%

EPSS percentile

Yes

Actively exploited

Ransomware use

2023-03-10

Added

MITRE ATT&CK techniques

How this vulnerability maps to adversary behaviour, from the Center for Threat-Informed Defense's public CVE→ATT&CK mappings. Use it to check whether your detections already cover the technique.

Technique	Name	Relationship
T1190	Exploit Public-Facing Application	exploitation technique
T1203	Exploitation for Client Execution	primary impact

Summary

XStream contains a remote code execution vulnerability that allows an attacker to manipulate the processed input stream and replace or inject objects that result in the execution of a local command on the server. This vulnerability can affect multiple products, including but not limited to VMware Cloud Foundation.

Affected software

Vendor: XStream · Product: XStream

Weakness types (CWE):

What to do

This vulnerability appears in CISA's Known Exploited Vulnerabilities catalog, meaning it is being exploited in the wild. Prioritize patching affected systems and verify exposure across your estate.

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All information is aggregated from public sources for awareness only and does not constitute an accusation or a security assessment. No personal data or credentials are published.