CVE-2009-0506 in WebSphere Application Server
Summary
by MITRE
Unspecified vulnerability in IBM WebSphere Application Server (WAS) 5.1 and 6.0.2 before 6.0.2.33 on z/OS, when CSIv2 Identity Assertion is enabled and Enterprise JavaBeans (EJB) interaction occurs between a WAS 6.1 instance and a WAS pre-6.1 instance, allows local users to have an unknown impact via vectors related to (1) use of the wrong subject and (2) multiple CBIND checks.
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Analysis
by VulDB Data Team • 08/04/2021
The vulnerability described in CVE-2009-0506 represents a critical security flaw within IBM WebSphere Application Server versions 5.1 and 6.0.2 prior to 6.0.2.33 running on z/OS operating systems. This issue specifically manifests when CSIv2 Identity Assertion is enabled and Enterprise JavaBeans interaction occurs between different WebSphere versions, creating a complex attack surface that exploits authentication and authorization mechanisms. The vulnerability's unspecified nature indicates the exact impact remains partially unclear, though the potential for privilege escalation or unauthorized access exists given the underlying authentication framework manipulation.
The technical flaw stems from improper handling of subject identification during EJB interactions between WebSphere 6.1 and pre-6.1 instances when CSIv2 Identity Assertion is active. The vulnerability exploits two primary vectors: incorrect subject usage and multiple CBIND checks that fail to properly validate authentication contexts. This creates a scenario where local users can manipulate the authentication flow to potentially gain elevated privileges or access unauthorized resources. The issue specifically relates to how the system handles identity assertions and subject validation during cross-version EJB communications, where the wrong subject is used in authentication contexts and CBIND checks are insufficiently enforced.
The operational impact of this vulnerability is significant for organizations running affected WebSphere versions, particularly in enterprise environments where legacy systems interact with newer components. Local users with access to the system can potentially exploit this weakness to perform unauthorized operations, compromise system integrity, or escalate privileges within the application server environment. The vulnerability's presence in z/OS environments adds complexity as it involves mainframe security contexts where traditional attack vectors may not apply. Organizations using mixed WebSphere version deployments for EJB communication are particularly at risk, as the flaw specifically targets these interoperability scenarios.
Security mitigations for this vulnerability should focus on immediate patching to IBM WebSphere Application Server 6.0.2.33 or later versions, which contain the necessary fixes for the CSIv2 Identity Assertion handling. Organizations should also consider disabling CSIv2 Identity Assertion when not required, particularly in environments where cross-version EJB interactions occur. Network segmentation and access controls should be implemented to limit local user privileges and reduce the potential impact of exploitation. System monitoring should be enhanced to detect anomalous authentication patterns or unauthorized subject switching during EJB interactions. This vulnerability aligns with CWE-284 (Improper Access Control) and may map to ATT&CK techniques involving privilege escalation and credential manipulation. Organizations should conduct thorough security assessments of their WebSphere deployments to identify and remediate similar cross-version compatibility issues that could present analogous security risks.