CVE-2009-2146 in SugarCRM
Summary
by MITRE
Unrestricted file upload vulnerability in the Compose Email feature in the Emails module in Sugar Community Edition (aka SugarCRM) before 5.2f allows remote authenticated users to execute arbitrary code by uploading a file with only an extension in its name, then accessing the file via a direct request to a modified filename under cache/modules/Emails/, as demonstrated using .php as the entire original name.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 08/28/2025
The vulnerability CVE-2009-2146 represents a critical unrestricted file upload flaw in Sugar Community Edition versions prior to 5.2f, specifically within the Emails module's Compose Email functionality. This issue enables authenticated attackers to bypass file validation mechanisms by exploiting a weakness in filename handling that only examines file extensions rather than content verification. The vulnerability stems from insufficient input sanitization and validation processes that fail to properly inspect uploaded files for malicious content, creating a pathway for arbitrary code execution through carefully crafted file uploads.
The technical implementation of this vulnerability occurs through a specific manipulation of file naming conventions where attackers can upload files with minimal or no actual filename content, using only extensions such as .php as the complete file designation. When the system processes these uploads, it stores them in the cache/modules/Emails/ directory structure, allowing subsequent direct access via modified filenames. This approach circumvents traditional file type checking mechanisms that typically validate file extensions against allowed lists, instead relying on a flawed assumption that extension-based validation alone provides adequate security. The vulnerability operates under CWE-434 which specifically addresses Unrestricted Upload of File with Dangerous Type, making it a direct implementation of this well-known security weakness.
The operational impact of this vulnerability is severe and far-reaching for organizations using affected SugarCRM versions, as it provides attackers with a straightforward path to achieve remote code execution on the target system. Once an authenticated user successfully uploads a malicious file, the attacker can execute arbitrary code with the privileges of the web application, potentially leading to complete system compromise, data exfiltration, or establishment of persistent backdoors. The attack vector requires only a valid user account, making it particularly dangerous as it can be exploited by insiders or through credential compromise. The direct request mechanism allows attackers to execute their payloads without requiring complex exploitation techniques, as the uploaded files become immediately accessible through predictable paths within the cache structure.
Organizations should implement multiple layers of defense to mitigate this vulnerability, beginning with immediate patching to versions 5.2f or later where the file upload validation has been properly strengthened. The mitigation strategy should include implementing strict file type validation that examines both file extensions and content signatures, rather than relying solely on extension checks. Network segmentation and web application firewalls can provide additional protection by monitoring and blocking suspicious file upload patterns. Access controls should be enforced to limit upload capabilities to only trusted administrative users, while regular security audits should verify that no malicious files remain in the cache directories. The remediation process must also include monitoring for any unauthorized file uploads and implementing proper file access controls to prevent direct execution of uploaded files, aligning with ATT&CK technique T1190 for exploiting vulnerabilities in web applications.