XStream XStream
YES - ON THE CISA KEV LIST
CVE-2021-39144
XStream Remote Code Execution Vulnerability
overdue since 2023-03-31
XStream: 1 entries (0.1% of all KEV entries are from this vendor); 0 added in 2026.
BOD 26-04 note: this is the date printed in the CISA catalog. A federal agency's actual deadline is set by its SSVC tier - Act (3 days), Attend (14 days), Track (60 days), or the next scheduled upgrade - counted from the KEV listing date or the date the vulnerability is identified in its environment, whichever comes first. Use the tier helper on each CVE page for your own window.
Your BOD 26-04 window (SSVC tier helper)
Your remediation window ends:
Description
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.
Required action (CISA)
Apply updates per vendor instructions.
Notes
https://www.vmware.com/security/advisories/VMSA-2022-0027.html, https://x-stream.github.io/CVE-2021-39144.html; https://nvd.nist.gov/vuln/detail/CVE-2021-39144
References
Other KEV entries for this vendor: XStream
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