CVE-2015-2946 in SXF Common Library
Summary
by MITRE
Stack-based buffer overflow in the Open CAD Format Council SXF common library before 3.30 allows remote attackers to execute arbitrary code via a crafted CAD file.
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Analysis
by VulDB Data Team • 03/31/2019
The vulnerability CVE-2015-2946 represents a critical stack-based buffer overflow within the Open CAD Format Council SXF common library version 3.29 and earlier. This flaw exists in the processing of CAD files that utilize the SXF format, which is commonly used for exchanging computer-aided design data between different software applications. The vulnerability stems from insufficient input validation and bounds checking when parsing maliciously crafted CAD files that contain oversized data structures within the SXF file format.
The technical implementation of this vulnerability occurs during the parsing of CAD files where the SXF library fails to properly validate the size of data elements before copying them into fixed-size stack buffers. When an attacker crafts a malicious CAD file containing oversized data fields, the library attempts to copy this data into a stack buffer that is too small to accommodate the incoming data, resulting in a buffer overflow condition. This overflow corrupts adjacent stack memory, potentially allowing an attacker to overwrite return addresses and function pointers, thereby gaining control over the program execution flow.
From an operational perspective, this vulnerability poses significant risks to organizations that rely on CAD software for design and engineering workflows. The remote execution aspect means attackers can exploit this vulnerability without requiring local access to systems, making it particularly dangerous in enterprise environments where CAD files are frequently shared between different departments and external partners. The impact extends beyond simple code execution to potentially allow privilege escalation and persistence mechanisms, as attackers could leverage this vulnerability to establish backdoors within design environments that may contain sensitive intellectual property.
The vulnerability maps directly to CWE-121 Stack-based Buffer Overflow, which is categorized under the Common Weakness Enumeration framework as a fundamental flaw in memory management. This weakness is particularly concerning in the context of the ATT&CK framework where it would be classified under the T1059.007 technique for Command and Scripting Interpreter, specifically through the exploitation of vulnerable applications. The attack surface is broad as any application that utilizes the affected SXF library for CAD file processing could be targeted, including various CAD software suites, engineering design platforms, and document management systems.
Mitigation strategies for this vulnerability require immediate patching of all affected systems and applications that utilize the SXF library version 3.29 or earlier. Organizations should implement strict file validation policies that reject CAD files from untrusted sources and consider implementing sandboxing mechanisms for CAD file processing. Network segmentation and access controls should be enhanced to limit exposure of systems that process CAD files, while regular security assessments should be conducted to identify other potential vulnerabilities in CAD processing pipelines. Additionally, application whitelisting and monitoring for unusual file processing activities can help detect potential exploitation attempts. The remediation process should also include comprehensive testing of patched libraries to ensure that the vulnerability is fully resolved without introducing regressions in functionality.