CVE-2015-3248 in OpenHPI
Summary
by MITRE
openhpi/Makefile.am in OpenHPI before 3.6.0 uses world-writable permissions for /var/lib/openhpi directory, which allows local users, when quotas are not properly setup, to fill the filesystem hosting /var/lib and cause a denial of service (disk consumption).
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Analysis
by VulDB Data Team • 12/30/2022
The vulnerability identified as CVE-2015-3248 affects the OpenHPI (Open Hardware Platform Interface) software suite, specifically within the Makefile.am configuration file that governs the installation process of the system. This issue represents a fundamental security flaw in the permission handling mechanism of the software's installation procedure, where the /var/lib/openhpi directory is created with world-writable permissions. The vulnerability exists in OpenHPI versions prior to 3.6.0, making all earlier releases susceptible to exploitation by local attackers who have access to the system. The flaw demonstrates poor privilege management and inadequate security hardening practices that are commonly associated with weak file system permission configurations.
The technical nature of this vulnerability stems from the improper assignment of file system permissions during the software installation process. When OpenHPI is installed on a system, the Makefile.am script creates the /var/lib/openhpi directory with permissions that allow any user on the system to write to this location. This world-writable permission setting creates a significant security risk because it enables any local user to place files within this directory regardless of their privileges. The vulnerability is particularly dangerous because it can be exploited even when the system has proper quota enforcement mechanisms in place, as the flaw specifically mentions that the issue occurs when quotas are not properly configured, suggesting that the vulnerability may persist even under normal operational conditions where quotas should prevent such abuse.
The operational impact of this vulnerability is severe and directly related to resource exhaustion and denial of service conditions. Local users can exploit this flaw by continuously writing data to the world-writable /var/lib/openhpi directory, potentially consuming all available disk space on the filesystem that hosts /var/lib. This disk consumption attack can lead to a complete denial of service situation where the system becomes unresponsive due to lack of available storage space, affecting not only the OpenHPI service but potentially other system functions that depend on the availability of disk resources. The vulnerability is particularly concerning in multi-user environments where unprivileged users might gain access to the system through various attack vectors and then leverage this weakness to cause system-wide disruptions.
This vulnerability aligns with CWE-732: Incorrect Permission Assignment for Critical Resource, which specifically addresses situations where critical system resources are assigned incorrect permissions that allow unauthorized access or modification. The flaw also maps to ATT&CK technique T1499.001: Network Denial of Service, as it enables local users to consume system resources in a manner that can cause service disruption. Additionally, the vulnerability demonstrates characteristics of privilege escalation through resource exhaustion, which can be categorized under ATT&CK technique T1072: Software Deployment Tools. The issue represents a classic case of inadequate access control implementation and poor system hardening practices that leave critical system directories vulnerable to unauthorized modifications by local users.
The recommended mitigation strategy involves upgrading to OpenHPI version 3.6.0 or later, where the installation process properly sets restrictive permissions for the /var/lib/openhpi directory. System administrators should also implement proper filesystem quota enforcement to limit the amount of disk space that individual users can consume, thereby reducing the potential impact of this vulnerability even if the software upgrade is not immediately possible. Additionally, regular security audits should be conducted to ensure that no other system directories have been configured with world-writable permissions, as this vulnerability demonstrates the importance of maintaining proper file system permission controls. Organizations should also consider implementing monitoring solutions that can detect unusual disk space consumption patterns that might indicate exploitation of this vulnerability.