CVE-2017-18397 in cPanel
Summary
by MITRE
cPanel before 68.0.15 does not preserve permissions for local backup transport (SEC-330).
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Analysis
by VulDB Data Team • 07/18/2020
The vulnerability identified as CVE-2017-18397 affects cPanel versions prior to 68.0.15 and specifically relates to the improper handling of file permissions during local backup transport operations. This issue falls under the broader category of permission management flaws that can lead to unauthorized access to sensitive system data. The vulnerability is particularly concerning because it impacts the integrity and confidentiality of backup files that contain critical system information and user data. When cPanel performs local backup operations, it should maintain the original file permissions to ensure that sensitive files remain protected according to their intended access controls. However, this flaw causes the system to strip or reset permissions during the backup transport process, potentially exposing sensitive files to unauthorized access or modification.
The technical implementation of this vulnerability stems from cPanel's backup transport mechanism failing to properly preserve file attributes when moving files between directories or storage locations. This issue is classified under CWE-276 which addresses improper file permissions and can be exploited by attackers who gain access to the system to manipulate backup files. The flaw occurs during the local transport process where cPanel's backup functionality does not correctly maintain the original file permission bits, which can include read, write, and execute permissions for different user groups. This misconfiguration creates a scenario where backup files may be accessible to users or processes that should not have such access, potentially leading to data leakage or system compromise.
The operational impact of this vulnerability extends beyond simple permission mismanagement and can significantly affect system security posture and compliance requirements. Organizations using affected cPanel versions may find that their backup files contain sensitive information such as database credentials, configuration files, and user data that are accessible with reduced permissions. This exposure can lead to privilege escalation attacks where attackers exploit the weakened permissions to gain deeper system access. The vulnerability can also impact regulatory compliance requirements for data protection, particularly in environments governed by standards such as pci dss, hipaa, or soc 2, where proper file permissions are mandatory for maintaining data security. Additionally, the issue can create audit trail complications as backup files may not accurately reflect the original security configuration of the system.
Mitigation strategies for CVE-2017-18397 primarily involve upgrading to cPanel version 68.0.15 or later where the permission preservation issue has been addressed. System administrators should also implement additional monitoring controls to detect unauthorized changes to backup files and their permissions. The remediation process should include verifying that backup operations maintain proper file attributes and conducting regular audits of backup storage directories to ensure that permission settings remain intact. Organizations should also review their backup policies and procedures to ensure that sensitive files are properly protected even when they are part of backup operations. Security teams should consider implementing automated permission checking tools that can alert administrators when backup files exhibit unexpected permission changes, aligning with the principle of least privilege and proper access control enforcement. The vulnerability demonstrates the importance of maintaining consistent security controls across all system operations including backup and restore processes, as highlighted in the mitre att&ck framework under the privilege escalation and defense evasion techniques that can be facilitated by such permission flaws.