CVE-2017-18285 in Burp
Summary
by MITRE
The Gentoo app-backup/burp package before 2.1.32 has incorrect group ownership of the /etc/burp directory, which might allow local users to obtain read and write access to arbitrary files by leveraging access to a certain account for a burp-server.conf change.
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Analysis
by VulDB Data Team • 03/21/2023
The vulnerability identified as CVE-2017-18285 affects the Gentoo app-backup/burp package version prior to 2.1.32, presenting a significant privilege escalation risk through improper file system permissions. This issue stems from incorrect group ownership of the /etc/burp directory, which creates a pathway for local attackers to gain unauthorized access to sensitive system files. The burp backup software is designed for enterprise backup solutions and typically requires elevated privileges to function correctly, making this vulnerability particularly concerning for systems where it is deployed.
The technical flaw manifests in the package's installation process where the /etc/burp directory is created with insufficient group permissions, allowing any user with access to a specific account to modify the burp-server.conf file. This misconfiguration enables attackers to manipulate the server configuration in ways that could grant them read and write access to arbitrary files within the system. The vulnerability operates through a privilege escalation vector where a low-privileged user can leverage their access to a particular account to make changes that ultimately compromise file system integrity and confidentiality.
The operational impact of this vulnerability extends beyond simple file access, as it represents a critical weakness in the principle of least privilege that is fundamental to secure system administration. Attackers could potentially use this vulnerability to access sensitive backup configurations, modify backup schedules, or even gain access to backup data that might contain confidential information. The attack surface is particularly wide since the burp package is commonly used in enterprise environments where backup systems contain valuable data assets. This vulnerability directly relates to CWE-732, which addresses incorrect permission assignment, and aligns with ATT&CK technique T1068, which covers privilege escalation through local service manipulation.
Mitigation strategies for this vulnerability should focus on immediate package updates to version 2.1.32 or later, where the group ownership permissions have been corrected. System administrators should also conduct thorough audits of the /etc/burp directory permissions to ensure that no other similar misconfigurations exist. Additional protective measures include implementing proper access controls for accounts that might be used to modify burp-server.conf files, utilizing mandatory access controls where possible, and monitoring for unauthorized changes to backup configuration files. Regular security assessments should verify that backup system permissions align with security best practices and that privilege escalation vectors are properly addressed through proper access control mechanisms.