XStream Remote Code Execution Vulnerability
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.
A remote attacker, with a low-privilege account, can achieve full data confidentiality loss, arbitrary modification of data, complete denial of service or system unavailability. Federal agencies are required to remediate by 2023-03-31 under CISA BOD 22-01.
This is a Code Injection (CWE-94) vulnerability in XStream XStream. XStream is a simple library to serialize objects to XML and back again. In affected versions this vulnerability may allow a remote attacker 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. XStream 1.4.18 uses no longer a blacklist by default, since it cannot be secured for general purpose. Exploitation requires remote network access, higher attack complexity, a low-privilege authenticated account, and no user interaction required.
Probably yes if any of these apply:
Active exploitation documented in the wild. Threat-research write-up: http://packetstormsecurity.com/files/169859/VMware-NSX-Manager-XStream-Unauthenticated-Remote-Code-Execution.html
Manual remediation steps
Apply the Vendor Patch
This vulnerability is in the CISA Known Exploited Vulnerabilities catalog — apply the vendor's security update as soon as possible.
CISA required action: Apply updates per vendor instructions.
References
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References