CVE-2021-39458 in Redaxo CMS
Summary
by MITRE • 09/09/2021
Triggering an error page of the import process in Yakamara Media Redaxo CMS version 5.12.1 allows an authenticated CMS user has to alternate the files of a vaild file backup. This leads of leaking the database credentials in the environment variables.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 09/12/2021
The vulnerability CVE-2021-39458 affects Yakamara Media Redaxo CMS version 5.12.1 and represents a critical security flaw that exploits an error handling mechanism during the import process. This vulnerability specifically targets authenticated users who can manipulate file backups through the CMS interface, creating a path for privilege escalation and sensitive data exposure. The flaw exists within the application's error page handling system where improper validation allows users to alter valid file backup contents, ultimately compromising the database credentials stored in environment variables.
The technical implementation of this vulnerability stems from inadequate input validation and insufficient access controls during the import process. When an error occurs during file import operations, the system fails to properly sanitize user inputs or validate file integrity checks. This allows an authenticated attacker to substitute legitimate backup files with malicious ones, leveraging the CMS's error handling mechanism to execute unauthorized file modifications. The vulnerability is classified as a path traversal or file manipulation issue under CWE-22, where improper validation of file paths or contents enables unauthorized access to system resources.
The operational impact of this vulnerability extends beyond simple file manipulation, as it directly compromises database credential exposure through environment variable leakage. When an attacker successfully alters the backup files, they can potentially access database connection strings, passwords, and other sensitive configuration data that are typically stored in environment variables for application runtime access. This exposure creates a significant risk for data breaches, unauthorized database access, and potential lateral movement within affected networks. The attack vector requires authentication but does not need elevated privileges, making it particularly dangerous in environments where multiple users have CMS access.
From a cybersecurity perspective, this vulnerability aligns with ATT&CK technique T1552.001 for unsecured credentials and T1078.004 for valid accounts, as it leverages legitimate user credentials to access sensitive information. The flaw represents a privilege escalation vulnerability that could be exploited by malicious insiders or compromised accounts. Organizations using Redaxo CMS version 5.12.1 should immediately implement mitigation strategies including restricting file import permissions, implementing strict backup file validation, and monitoring for unauthorized file modifications. Regular security audits of CMS error handling mechanisms and comprehensive environment variable management practices are essential to prevent exploitation of similar vulnerabilities. The vulnerability highlights the importance of proper input validation and access control implementation in web applications, particularly those handling sensitive data and configuration files.