CVE-2022-35741 in CloudStack
Summary
by MITRE • 07/18/2022
Apache CloudStack version 4.5.0 and later has a SAML 2.0 authentication Service Provider plugin which is found to be vulnerable to XML external entity (XXE) injection. This plugin is not enabled by default and the attacker would require that this plugin be enabled to exploit the vulnerability. When the SAML 2.0 plugin is enabled in affected versions of Apache CloudStack could potentially allow the exploitation of XXE vulnerabilities. The SAML 2.0 messages constructed during the authentication flow in Apache CloudStack are XML-based and the XML data is parsed by various standard libraries that are now understood to be vulnerable to XXE injection attacks such as arbitrary file reading, possible denial of service, server-side request forgery (SSRF) on the CloudStack management server.
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Analysis
by VulDB Data Team • 08/06/2022
The vulnerability identified as CVE-2022-35741 affects Apache CloudStack versions 4.5.0 and later, specifically within the SAML 2.0 authentication Service Provider plugin. This represents a critical security flaw that exploits XML external entity injection vulnerabilities, which fall under the CWE-611 classification for XML External Entity Processing. The vulnerability exists in the authentication flow where SAML 2.0 messages are constructed and processed, making it particularly dangerous as it targets the core authentication mechanisms of the cloud infrastructure platform. The XXE vulnerability is not automatically active since the plugin requires manual enabling, but once activated, it creates a significant attack surface for malicious actors targeting cloud management systems.
The technical exploitation of this vulnerability occurs through the parsing of XML data during SAML authentication processes. When the SAML 2.0 plugin is enabled, the CloudStack management server processes XML-based authentication messages using standard XML libraries that have been identified as susceptible to XXE injection attacks. This parsing behavior allows attackers to manipulate the XML processing to access internal system resources, potentially leading to unauthorized data access, file system enumeration, and privilege escalation. The vulnerability specifically enables attackers to perform arbitrary file reading operations against the management server, which could expose sensitive configuration files, credentials, and other critical system information.
The operational impact of CVE-2022-35741 extends beyond simple data exposure to include potential denial of service conditions and server-side request forgery attacks. Attackers could leverage the XXE vulnerability to perform SSRF against internal network services, potentially bypassing firewall restrictions and accessing backend systems that would normally be isolated from external network traffic. This capability significantly expands the attack surface and could enable lateral movement within cloud environments, particularly in multi-tenant deployments where CloudStack manages multiple customer workloads. The vulnerability affects the core management plane of CloudStack, making it particularly dangerous for organizations that rely on this platform for their cloud infrastructure operations.
Organizations should implement immediate mitigations including disabling the SAML 2.0 plugin if it is not actively required for their authentication workflows, which aligns with the principle of least privilege and defense in depth strategies. The recommended approach involves updating to patched versions of Apache CloudStack where the XXE vulnerability has been addressed through proper XML parsing controls and input validation mechanisms. Security configurations should include disabling external entity processing in all XML parsers used by the CloudStack management server, implementing proper network segmentation to limit access to management interfaces, and conducting regular security assessments of authentication plugins. Additionally, organizations should monitor for any unauthorized enabling of the SAML plugin and implement automated alerting for suspicious authentication activities that could indicate exploitation attempts, following ATT&CK framework techniques for credential access and privilege escalation.