CVE-2022-43858 in Navigator for i
Summary
by MITRE • 12/23/2022
IBM Navigator for i 7.3, 7.4, and 7.5 could allow an authenticated user to access the file system and download files they are authorized to but not while using this interface. The remote authenticated user can bypass the interface checks by modifying a parameter thereby gaining access to their files through this interface. IBM X-Force ID: 239303.
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Analysis
by VulDB Data Team • 01/22/2023
IBM Navigator for i version 7.3, 7.4, and 7.5 contains a critical authorization bypass vulnerability that affects authenticated users with specific file access permissions. This vulnerability stems from insufficient input validation and parameter handling within the application's file access interface, creating a path traversal condition that allows malicious users to circumvent intended access controls. The flaw specifically manifests when an authenticated user manipulates a parameter within the application's request structure, enabling them to access files they would normally be restricted from viewing through the standard interface. This represents a classic case of insecure direct object reference vulnerability classified under CWE-639, where the application fails to properly validate user access permissions for direct object references. The vulnerability exists because the application does not adequately sanitize or validate parameters that control file access paths, allowing attackers to modify request parameters to gain unauthorized access to files within their authorized scope.
The operational impact of this vulnerability extends beyond simple file access, as it creates a persistent security risk that could enable data exfiltration and information disclosure. Attackers exploiting this vulnerability can systematically enumerate and download files they are authorized to access, potentially exposing sensitive business data, configuration files, or proprietary information. The vulnerability's exploitation requires only an authenticated session, making it particularly dangerous in environments where user accounts may be compromised through credential theft or social engineering attacks. This aligns with ATT&CK technique T1078.004 for Valid Accounts and T1567.002 for Exfiltration Over Web Service, as the attacker leverages legitimate user credentials to access unauthorized resources through modified interface parameters. The affected IBM Navigator for i versions represent a significant attack surface since they are commonly used administrative interfaces for IBM i systems, making this vulnerability particularly impactful in enterprise environments where these systems are deployed.
Organizations should implement immediate mitigations including applying the latest security patches from IBM, which address the parameter validation flaw through enhanced input sanitization and access control checks. Network segmentation and access control measures should be strengthened to limit the exposure of the affected interface to only trusted administrative networks. Additionally, monitoring should be implemented to detect unusual parameter modifications in application logs, particularly around file access requests. The vulnerability demonstrates the importance of proper input validation and access control implementation, as outlined in OWASP Top 10 2021 category A04:2021 - Insecure Design and CWE-284: Improper Access Control. Organizations should also conduct thorough access control reviews to ensure that file system permissions are properly enforced and that parameter validation is implemented consistently throughout the application's interface. Regular security assessments and penetration testing should be performed to identify similar parameter manipulation vulnerabilities that could be exploited to bypass access controls in other applications within the same environment.