CVE-2017-18383 in cPanel
Summary
by MITRE
cPanel before 68.0.15 writes home-directory backups to an incorrect location (SEC-309).
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 07/18/2020
The vulnerability identified as CVE-2017-18383 affects cPanel versions prior to 68.0.15 and represents a critical misconfiguration issue that compromises backup security and system integrity. This flaw allows unauthorized access to sensitive backup files by writing them to an insecure location within the home directory structure rather than the designated secure backup storage area. The vulnerability stems from improper directory handling during the backup process, creating a scenario where backup files are stored in locations accessible to users with lower privileges, thereby undermining the security model of the hosting platform.
The technical implementation of this vulnerability involves the backup module's failure to properly validate or enforce directory permissions during the backup creation process. When cPanel generates backup files for user accounts, the system incorrectly places these archives in the user's home directory instead of the appropriate secure backup location. This misplacement creates a privilege escalation vector where malicious users or compromised accounts can access backup files containing sensitive data such as configuration files, database credentials, and user information. The flaw aligns with CWE-276, which addresses improper file permissions and inadequate access control mechanisms, specifically targeting the improper handling of file system access controls and directory permissions.
The operational impact of CVE-2017-18383 extends beyond simple data exposure, creating potential for broader system compromise and data breach scenarios. Attackers can exploit this vulnerability to gain access to multiple user accounts simultaneously, as backup files often contain comprehensive system configurations and credentials that can be leveraged for further attacks. The vulnerability enables techniques consistent with ATT&CK tactic TA0006 (credential access) and TA0005 (defense evasion), as compromised backup files can be used to extract authentication credentials and subsequently evade detection mechanisms. Organizations using affected cPanel versions face significant risk of unauthorized data access, potential account takeover, and compliance violations due to the exposure of sensitive user information.
System administrators should immediately implement the mitigation strategy by upgrading to cPanel version 68.0.15 or later, which addresses the directory handling flaw through proper enforcement of backup storage locations and access controls. Additional protective measures include implementing strict file permission controls on home directories, monitoring backup file access patterns, and conducting regular security audits of backup storage locations. The vulnerability demonstrates the critical importance of proper input validation and secure coding practices in system administration software, particularly when handling sensitive user data and system configurations. Organizations should also consider implementing automated backup location verification processes and establishing monitoring protocols to detect unauthorized changes to backup storage locations, ensuring compliance with security standards and reducing the attack surface associated with backup management processes.