CVE-1999-1308 in HP-UX
Summary
by MITRE
Certain programs in HP-UX 10.20 do not properly handle large user IDs (UID) or group IDs (GID) over 60000, which could allow local users to gain privileges.
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Analysis
by VulDB Data Team • 04/16/2026
The vulnerability identified as CVE-1999-1308 represents a critical privilege escalation flaw affecting HP-UX 10.20 systems where certain programs fail to properly handle user identifiers exceeding 60000. This issue stems from the operating system's inadequate validation of large UID and GID values, creating a pathway for local attackers to exploit the system's permission model. The flaw specifically manifests in programs that process user authentication and authorization data, where the system's internal handling of identifiers beyond the conventional range allows for unexpected behavior that can be leveraged for unauthorized access.
The technical root cause of this vulnerability lies in the insufficient bounds checking within HP-UX system utilities and daemons that process user account information. When UIDs and GIDs exceed 60000, the programs in question do not properly validate or sanitize these large values, leading to potential integer overflow conditions or improper access control decisions. This misconfiguration allows local users to manipulate their account identifiers to bypass normal security restrictions and gain elevated privileges. The vulnerability operates under the broader category of improper input validation, which aligns with CWE-20, and represents a classic example of how system-level programming errors can create security weaknesses that directly impact the core privilege model.
From an operational impact perspective, this vulnerability enables local users to escalate their privileges from standard user level to administrative access without requiring authentication. Attackers can exploit this by creating or manipulating user accounts with large UIDs, potentially allowing them to bypass file permissions, access restricted system resources, or modify critical system files. The impact extends beyond simple privilege escalation as it can enable attackers to establish persistent access to the system, modify system configurations, or even compromise the integrity of the entire operating environment. This vulnerability particularly affects systems where local users might have legitimate access but should not possess administrative capabilities.
The mitigation strategies for CVE-1999-1308 should focus on immediate system updates and configuration hardening. HP-UX administrators should apply the relevant security patches provided by Hewlett Packard to address the specific handling of large UID and GID values in affected programs. Additionally, system administrators should implement strict monitoring of user account creation and modification activities, particularly for accounts with unusual UID ranges. The implementation of proper input validation controls and the enforcement of minimum and maximum UID/GID boundaries can help prevent exploitation of this vulnerability. Organizations should also consider implementing the principle of least privilege and regularly audit user account permissions to minimize the potential impact of such vulnerabilities. This remediation approach aligns with ATT&CK technique T1068 which covers privilege escalation through local exploits and follows the security principle of defense in depth as outlined in NIST SP 800-53.