CVE-2017-2918 in 3d Creation Suite
Summary
by MITRE
An exploitable integer overflow exists in the Image loading functionality of the Blender open-source 3d creation suite v2.78c. A specially crafted .blend file can cause an integer overflow resulting in a buffer overflow which can allow for code execution under the context of the application. An attacker can convince a user to open the file or use it as a library in order to trigger this vulnerability.
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Analysis
by VulDB Data Team • 03/07/2023
The vulnerability identified as CVE-2017-2918 represents a critical security flaw within the Blender 3D creation suite version 2.78c, specifically within its image loading functionality. This issue stems from an integer overflow condition that occurs when processing specially crafted .blend files, which are the native file format used by Blender for storing 3D scenes and projects. The flaw exists in the way the application handles memory allocation for image data structures, creating a scenario where malformed input can lead to unintended memory behavior. The vulnerability is particularly concerning because it allows for arbitrary code execution when the affected application processes the malicious file, potentially giving attackers complete control over the system running the vulnerable software.
The technical implementation of this vulnerability involves an integer overflow within the image loading code path where the application calculates buffer sizes based on user-supplied data from the .blend file. When the input data contains values that exceed the maximum representable value for the integer type being used, the overflow causes the calculation to wrap around to a much smaller value. This results in insufficient memory allocation for the buffer that should contain the actual image data, leading to a subsequent buffer overflow condition. The CWE-190 classification applies here as this represents an integer overflow vulnerability where the result of an integer computation is used as the size of a buffer, directly enabling buffer overflow conditions that can be exploited for code execution.
The operational impact of this vulnerability extends beyond simple denial of service scenarios, as it creates a full code execution vector that can be leveraged by attackers to compromise systems running vulnerable versions of Blender. The attack requires social engineering to convince a user to open the malicious .blend file, but once executed, the consequences are severe as the attacker gains the same privileges as the application itself. This vulnerability affects not only individual users but also organizations that rely on Blender for professional 3D work, as the attack vector can be embedded in legitimate project files or used as library components in larger projects. The ATT&CK framework categorizes this as a privilege escalation technique through application execution, where the attacker leverages a legitimate application to execute malicious code, potentially leading to persistent access or further network compromise.
Mitigation strategies for CVE-2017-2918 should prioritize immediate software updates to versions that have patched the integer overflow condition, as the vulnerability exists in the specific version 2.78c and earlier releases. Organizations should implement strict file validation procedures for .blend files received from external sources, particularly in collaborative environments where project files are shared between multiple users. Network-based controls such as file content filtering and sandboxing techniques can provide additional protection layers, while user education regarding the risks of opening untrusted 3D files remains essential. The fix implemented by the Blender development team typically involves proper input validation and bounds checking for integer calculations used in memory allocation, ensuring that calculated buffer sizes remain within safe limits and preventing the overflow condition from occurring in the first place.