CVE-2006-1509 in HP-UX
Summary
by MITRE
/sbin/passwd in HP-UX B.11.00, B.11.11, and B.11.23 before 20060326 "does not recover gracefully from some error conditions," which allows local users to cause a denial of service.
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Analysis
by VulDB Data Team • 06/22/2025
The vulnerability identified as CVE-2006-1509 affects the /sbin/passwd utility on Hewlett-Packard Unix operating systems versions B.11.00, B.11.11, and B.11.23 prior to the 20060326 security patch release. This flaw represents a classic denial of service condition that occurs when the passwd command encounters certain error scenarios without proper error handling mechanisms. The issue specifically manifests in the password management utility's inability to gracefully recover from exceptional conditions, leading to system instability and service disruption. The vulnerability is particularly concerning because it affects a core system utility that handles user authentication and authorization processes, making it a critical component for system security and availability.
The technical root cause of this vulnerability lies in the insufficient error recovery mechanisms within the passwd command implementation. When the utility encounters specific error conditions during password modification operations, it fails to properly terminate or reset its internal state, resulting in a denial of service condition that can prevent legitimate users from performing password changes or accessing system authentication services. This behavior aligns with CWE-248, which describes an unchecked exception vulnerability where an application fails to properly handle exceptional conditions. The flaw demonstrates poor defensive programming practices where the system does not anticipate or properly manage error scenarios that could occur during normal operation, particularly in critical system utilities.
From an operational impact perspective, this vulnerability creates significant risks for system administrators and users who rely on password management functionality. Local attackers can exploit this weakness to disrupt normal system operations by triggering the denial of service condition, potentially preventing legitimate users from changing their passwords or accessing system resources. The attack surface is relatively narrow as it requires local system access, but the impact can be substantial given that the passwd utility is fundamental to system security operations. This vulnerability directly affects the availability and integrity of user authentication services, which can cascade into broader security implications. The issue is particularly dangerous in environments where automated password management or regular authentication updates are required, as it can effectively block legitimate administrative tasks.
The recommended mitigations for this vulnerability include applying the vendor-provided security patch released on 20060326, which addresses the specific error handling issues in the passwd utility. System administrators should prioritize patch deployment across all affected HP-UX systems to ensure proper error recovery mechanisms are in place. Additionally, monitoring for unusual system behavior or denial of service patterns related to password management should be implemented as part of security operations. Organizations should also consider implementing additional access controls and logging mechanisms around system utilities to detect potential exploitation attempts. The vulnerability demonstrates the importance of proper error handling in system utilities and aligns with ATT&CK technique T1499.004, which covers network denial of service, as the affected system utility can be manipulated to cause availability issues. Regular security assessments of core system utilities should be conducted to identify similar error handling deficiencies that could lead to similar denial of service conditions.