CVE-2026-1776 in Camaleon CMS
Summary
by MITRE • 03/10/2026
Camaleon CMS versions 2.4.5.0 through 2.9.0, prior to commit f54a77e, contain a path traversal vulnerability in the AWS S3 uploader implementation that allows authenticated users to read arbitrary files from the web server’s filesystem. The issue occurs in the download_private_file functionality when the application is configured to use the CamaleonCmsAwsUploader backend. Unlike the local uploader implementation, the AWS uploader does not validate file paths with valid_folder_path?, allowing directory traversal sequences to be supplied via the file parameter. As a result, any authenticated user, including low-privileged registered users, can access sensitive files such as /etc/passwd. This issue represents a bypass of the incomplete fix for CVE-2024-46987 and affects deployments using the AWS S3 storage backend.
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Analysis
by VulDB Data Team • 03/12/2026
The vulnerability described in CVE-2026-1776 represents a critical path traversal flaw within Camaleon CMS versions 2.4.5.0 through 2.9.0, specifically affecting deployments utilizing the AWS S3 storage backend. This security weakness stems from an improper validation mechanism in the CamaleonCmsAwsUploader implementation, which fails to properly sanitize user-supplied file paths during the download_private_file operation. The vulnerability is particularly concerning because it allows authenticated users to bypass normal access controls and read arbitrary files from the web server's filesystem, effectively creating a privilege escalation scenario that can be exploited by low-privileged registered users. The flaw manifests specifically when the application is configured to use the AWS S3 backend rather than the local uploader implementation, highlighting a design inconsistency in the security controls between different storage backends. This represents a significant regression since it bypasses the incomplete fix previously implemented for CVE-2024-46987, indicating that the remediation efforts were insufficient or improperly applied.
The technical implementation of this vulnerability exploits a fundamental security gap in the file path validation process within the AWS S3 uploader component. Unlike the local uploader which properly validates file paths through the valid_folder_path? method, the AWS uploader implementation omits this crucial validation step, allowing directory traversal sequences such as ../ or ..\ to be passed directly through the file parameter. This omission creates a direct pathway for attackers to manipulate the file access mechanism and traverse the filesystem hierarchy to access sensitive files that should normally be restricted. The vulnerability's impact extends beyond simple file reading capabilities, as it can potentially expose critical system information including configuration files, database credentials, application source code, and system-level files such as /etc/passwd that contain user account information. The flaw demonstrates a classic path traversal vulnerability pattern that aligns with CWE-22, which specifically addresses improper limitation of a pathname to a restricted directory, commonly referred to as directory traversal or path traversal attacks.
Operationally, this vulnerability presents a severe risk to organizations using Camaleon CMS with AWS S3 storage configurations, as it fundamentally undermines the application's security model and file access controls. The fact that any authenticated user, including those with minimal privileges, can exploit this vulnerability means that even registered users who should have limited access to the system can gain unauthorized access to sensitive data. This creates a significant attack surface that can be leveraged for further exploitation, including information disclosure, credential theft, and potential system compromise. The impact is particularly severe in environments where the CMS handles sensitive data or serves as a platform for multiple applications, as the vulnerability could potentially expose not only application-specific files but also system-level information that could be used to launch additional attacks. The bypass of the previous CVE-2024-46987 fix indicates that organizations may have believed they were protected against such vulnerabilities but remain exposed due to the incomplete remediation.
Organizations affected by this vulnerability should immediately implement multiple layers of mitigation strategies to protect their systems. The most critical immediate action is to upgrade to a patched version of Camaleon CMS that contains the proper validation logic for the AWS S3 uploader implementation, specifically ensuring that the fix addresses the path traversal issue without relying on the incomplete previous fix. Additionally, administrators should consider implementing network-level restrictions and access controls that limit access to the download_private_file functionality, particularly for authenticated users who do not require such capabilities. The implementation of proper input validation and sanitization measures within the application's file handling components should be enforced across all storage backends to prevent similar issues from occurring. Organizations should also conduct thorough security assessments of their CMS installations to identify any other potential path traversal vulnerabilities or similar security gaps in their web application architecture, as this vulnerability may indicate broader security design issues within the application's file access controls. The remediation process should include monitoring for any suspicious file access patterns and implementing logging mechanisms that can detect and alert on potential exploitation attempts.