CVE-1999-1311 in HP-UX
Summary
by MITRE
vulnerability in dtlogin and dtsession in hp-ux 10.20 and 10.10 allows local users to bypass authentication and gain privileges.
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Analysis
by VulDB Data Team • 04/16/2026
The vulnerability identified as CVE-1999-1311 represents a critical authentication bypass flaw affecting Hewlett-Packard Unix operating systems versions 10.10 and 10.20. This issue specifically targets the dtlogin and dtsession components of the HP-UX desktop environment, which are responsible for managing user authentication and session handling within the graphical user interface. The flaw stems from improper privilege checking mechanisms within these desktop components, creating a pathway for local attackers to circumvent the standard authentication procedures that normally protect system access. The vulnerability exists at the intersection of desktop environment security and system-level privilege management, making it particularly dangerous as it allows attackers to escalate their privileges without requiring external network access or complex exploitation techniques.
The technical root cause of this vulnerability lies in the insufficient validation of user credentials and privilege levels within the dtlogin and dtsession applications. When these components process authentication requests, they fail to properly verify that the requesting user possesses the necessary authorization levels to access protected system resources. This weakness manifests as a privilege escalation vector where local users can manipulate the authentication flow to gain elevated system privileges. The flaw is classified under CWE-284 as improper access control, specifically involving inadequate privilege checking mechanisms. The vulnerability allows attackers to bypass authentication by exploiting the way these desktop applications handle user sessions and credential validation, potentially enabling unauthorized access to system resources that should be restricted to authorized users.
The operational impact of CVE-1999-1311 extends beyond simple privilege escalation, creating significant security implications for HP-UX systems running affected versions. Local users who can exploit this vulnerability gain the ability to execute commands with elevated privileges, potentially allowing them to modify system files, install malicious software, or access sensitive data that would normally be protected by standard access controls. This vulnerability directly relates to the ATT&CK technique T1068 which involves exploiting legitimate credentials and privileges to gain system access, and T1548 which covers privilege escalation through legitimate system processes. The impact is particularly severe in multi-user environments where local users might attempt to exploit this weakness to gain unauthorized access to other users' accounts or system resources. Organizations running HP-UX 10.10 and 10.20 systems face potential compromise of their entire desktop environment security posture, as this vulnerability affects core components that manage user sessions and authentication.
Mitigation strategies for CVE-1999-1311 should focus on immediate patching of affected systems through HP's official security updates, which would address the privilege checking mechanisms in dtlogin and dtsession. System administrators should implement additional monitoring to detect unauthorized privilege escalation attempts and review system logs for suspicious authentication patterns. The vulnerability's classification as a local privilege escalation issue means that organizations should enforce strict access controls and limit local user access to critical system components. Network segmentation and privilege separation measures can help minimize the potential damage from exploitation. Additionally, implementing proper security awareness training for system administrators can help identify potential exploitation attempts. Organizations should also consider disabling unnecessary desktop environment components when they are not actively required, reducing the attack surface. The remediation process should include thorough testing of patches in controlled environments before deployment to ensure system stability and prevent service disruptions. Given the age of this vulnerability, organizations should prioritize upgrading to supported HP-UX versions that contain proper security fixes and ongoing support for security patches.