CVE-2006-5704 in NonStop Server
Summary
by MITRE
HP NonStop Server G06.29, when running Standard Security T6533G06 before T6533G06^ABK, does not properly evaluate access permissions to OSS directories when no optional ACL entry exists, which allows local users to read arbitrary files.
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Analysis
by VulDB Data Team • 04/26/2026
The vulnerability identified as CVE-2006-5704 affects HP NonStop Server versions running Standard Security T6533G06 before the T6533G06^ABK patch level. This represents a critical access control flaw within the operating system's security framework that specifically impacts how the system evaluates permissions for OSS (Open System Services) directories. The issue manifests when optional ACL (Access Control List) entries are absent from directory structures, creating a dangerous permission evaluation gap that local attackers can exploit to gain unauthorized access to sensitive data.
The technical root cause of this vulnerability lies in the improper handling of access control evaluation when optional ACL entries are missing from OSS directory structures. In standard security implementations, when an ACL entry does not exist for a specific user or group, the system should enforce strict default permissions that prevent unauthorized access. However, in the affected HP NonStop Server versions, the permission evaluation logic fails to properly enforce these default restrictions when optional ACL entries are absent, allowing local users to bypass normal access controls and read arbitrary files that should otherwise be protected.
This vulnerability operates at the operating system level and presents significant operational impact for organizations relying on HP NonStop Server environments. Local users who can exploit this flaw can potentially access confidential data, system configuration files, and other sensitive information that should be restricted to authorized personnel only. The implications extend beyond simple data theft as attackers could potentially discover system vulnerabilities, extract intellectual property, or gather information for further attacks. The local nature of the exploit means that attackers do not require network access or specialized external tools, making the vulnerability particularly concerning for environments where local access is difficult to control or monitor.
The vulnerability aligns with CWE-284, which describes improper access control issues in software systems, and represents a classic case of privilege escalation through flawed permission evaluation. From an ATT&CK framework perspective, this vulnerability maps to privilege escalation techniques where adversaries leverage system weaknesses to gain elevated access rights. Organizations should implement immediate patch management procedures to address this vulnerability by upgrading to the T6533G06^ABK release or later. Additionally, system administrators should conduct thorough access control reviews, implement monitoring for unauthorized file access attempts, and consider additional security controls such as file integrity monitoring and privilege access auditing to detect potential exploitation attempts. The remediation process should include comprehensive testing of the updated security configuration to ensure that legitimate access controls remain functional while the vulnerability is properly addressed.