CVE-2014-0481 in Django
Summary
by MITRE
The default configuration for the file upload handling system in Django before 1.4.14, 1.5.x before 1.5.9, 1.6.x before 1.6.6, and 1.7 before release candidate 3 uses a sequential file name generation process when a file with a conflicting name is uploaded, which allows remote attackers to cause a denial of service (CPU consumption) by unloading a multiple files with the same name.
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Analysis
by VulDB Data Team • 02/15/2022
The vulnerability identified as CVE-2014-0481 represents a critical security flaw in the Django web framework's file upload handling mechanism. This issue affects multiple versions of Django including 1.4.x before 1.4.14, 1.5.x before 1.5.9, 1.6.x before 1.6.6, and versions prior to release candidate 3 of Django 1.7. The core problem lies in how Django manages file naming conflicts during the upload process, creating a significant vector for denial of service attacks that can severely impact system performance and availability.
The technical flaw stems from Django's default configuration using a sequential file name generation approach when duplicate filenames are encountered during file uploads. When an attacker uploads multiple files with identical names, the system's file handling process becomes inefficient and resource-intensive. Each conflicting file upload triggers a sequential naming process that consumes excessive cpu cycles as the system attempts to resolve naming conflicts. This sequential processing mechanism creates a quadratic complexity issue where the time required to handle multiple uploads grows exponentially with the number of conflicting files, leading to substantial cpu consumption and system resource exhaustion.
From an operational perspective, this vulnerability enables remote attackers to execute denial of service attacks that can effectively cripple web applications relying on Django's default file upload handling. The attack requires minimal resources from the attacker who only needs to upload multiple files with the same name to trigger the problematic behavior. The impact extends beyond simple service disruption as the excessive cpu consumption can affect other system processes, potentially causing cascading failures that impact overall system stability and availability. This vulnerability particularly affects applications that allow user file uploads without proper validation or sanitization of filenames.
The vulnerability aligns with CWE-400, which addresses "Uncontrolled Resource Consumption" and specifically relates to improper handling of resource allocation in software systems. From an attack framework perspective, this issue maps to the MITRE ATT&CK technique T1499.004 for "Resource Hijacking" where attackers consume system resources to cause denial of service conditions. The sequential naming algorithm creates a predictable pattern that attackers can exploit systematically, making this vulnerability particularly dangerous in environments where file upload functionality is exposed to untrusted users.
Mitigation strategies for CVE-2014-0481 involve upgrading to patched versions of Django where the file upload handling has been improved to prevent sequential naming conflicts. Organizations should implement proper file naming strategies that use random or hash-based naming conventions to eliminate predictable sequential patterns. Additionally, application-level controls should be implemented to limit concurrent file uploads and establish resource quotas for upload operations. Security teams should also consider implementing monitoring and alerting for unusual cpu consumption patterns that may indicate exploitation attempts. The most effective long-term solution requires updating to Django versions 1.4.14, 1.5.9, 1.6.6, or later releases where the vulnerability has been properly addressed through improved file handling algorithms and resource management mechanisms.