CVE-2015-8832 in DotClear
Summary
by MITRE
Multiple incomplete blacklist vulnerabilities in inc/core/class.dc.core.php in Dotclear before 2.8.2 allow remote authenticated users with "manage their own media items" and "manage their own entries and comments" permissions to execute arbitrary PHP code by uploading a file with a (1) .pht, (2) .phps, or (3) .phtml extension.
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Analysis
by VulDB Data Team • 09/14/2025
The vulnerability CVE-2015-8832 represents a critical security flaw in the Dotclear content management system affecting versions prior to 2.8.2. This issue stems from inadequate input validation and file extension handling within the core application framework, specifically in the inc/core/class.dc.core.php file. The vulnerability manifests as multiple incomplete blacklist implementations that fail to properly restrict file uploads, creating a pathway for malicious code execution.
The technical flaw exploits the system's insufficient filtering mechanisms for file extensions, particularly allowing uploads with .pht, .phps, and .phtml extensions. These extensions are not adequately blocked in the security checks, enabling attackers to bypass intended restrictions. The vulnerability specifically targets users with limited permissions including "manage their own media items" and "manage their own entries and comments" capabilities, which demonstrates how privilege escalation can occur through file upload vectors. This weakness aligns with CWE-434, which addresses insecure file upload handling, and represents a classic case of incomplete input validation where the blacklist approach fails to account for all potentially dangerous file extensions.
The operational impact of this vulnerability is severe as it allows authenticated attackers to execute arbitrary PHP code on the target system. This capability enables full system compromise, data exfiltration, and potential lateral movement within the network. Attackers can upload malicious files that contain PHP code, which then gets executed by the web server when accessed, providing them with persistent access to the system. The vulnerability's exploitation requires only basic user permissions, making it particularly dangerous as it can be leveraged by users who should have limited access rights. This represents a significant deviation from the principle of least privilege and demonstrates how insufficient access controls can lead to complete system compromise.
Organizations using Dotclear versions prior to 2.8.2 should immediately implement the available security patches and updates to address this vulnerability. Additionally, administrators should review and strengthen their file upload restrictions by implementing whitelist-based validation rather than relying on blacklists. The mitigation strategy should include regular security audits of file upload mechanisms and monitoring for suspicious file uploads. This vulnerability also highlights the importance of following ATT&CK framework principles, particularly the techniques related to command and control through web shells and persistence mechanisms. System administrators should consider implementing additional security controls such as web application firewalls and file integrity monitoring to detect and prevent similar vulnerabilities from being exploited in the future.