CVE-2007-6249 in Portage
Summary
by MITRE
etc-update in Portage before 2.1.3.11 on Gentoo Linux relies on the umask to set permissions for the merge file, often resulting in permissions weaker than those of the original files, which might allow local users to obtain sensitive information by reading the merge file.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 08/01/2019
The vulnerability identified as CVE-2007-6249 affects the Portage package management system in Gentoo Linux distributions prior to version 2.1.3.11. This issue specifically targets the etc-update utility which is responsible for handling configuration file updates during package installations and upgrades. The core problem lies in how the utility manages file permissions during the merge process, creating a security risk that could potentially expose sensitive system information to unauthorized local users.
The technical flaw stems from the improper handling of file permissions through the umask mechanism within the etc-update utility. When Portage processes configuration files during package updates, it creates temporary merge files that should maintain the same security characteristics as the original files. However, due to the reliance on umask settings, these merge files often end up with weaker permissions than their source counterparts. This discrepancy creates a window of opportunity for local attackers who can potentially read the merge files and extract sensitive information that might be present in configuration files or their temporary copies.
This vulnerability operates under the principle of information disclosure through improper access control mechanisms, which aligns with CWE-200 - Information Exposure and potentially CWE-732 - Incorrect Permission Assignment for Critical Resources. The operational impact extends beyond simple information leakage as configuration files often contain database credentials, API keys, system passwords, or other sensitive data that could be exploited by malicious actors. The weakness becomes particularly dangerous in environments where configuration files contain authentication tokens or other confidential information that should remain protected from unauthorized access.
The security implications of this vulnerability are significant for local users who can exploit the permission weakness to gain access to sensitive information that should remain protected. Attackers could potentially read merge files containing system configuration data, authentication credentials, or other confidential information that was intended to be restricted. This represents a direct violation of the principle of least privilege and could lead to further exploitation opportunities if the read data includes authentication tokens or system access credentials.
Mitigation strategies for CVE-2007-6249 should focus on updating to Portage version 2.1.3.11 or later, which contains the necessary fixes to properly handle file permissions during the merge process. System administrators should also implement regular security audits to identify and remediate similar permission-related vulnerabilities in other system components. Additional protective measures include monitoring for unauthorized access to configuration files and implementing proper file permission controls that ensure sensitive data remains protected throughout the package management lifecycle. The fix addresses the underlying ATT&CK technique T1005 - Data from Local System, which focuses on collecting information from the local system, and helps prevent unauthorized information disclosure through improper file access controls.