CVE-2016-7513 in ImageMagick
Summary
by MITRE
Off-by-one error in magick/cache.c in ImageMagick allows remote attackers to cause a denial of service (segmentation fault) via unspecified vectors.
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Analysis
by VulDB Data Team • 11/19/2024
The vulnerability identified as CVE-2016-7513 represents a critical off-by-one error within the ImageMagick image processing library, specifically located in the magick/cache.c source file. This flaw manifests as a boundary condition error that occurs during the handling of image data structures, where the software fails to properly validate array indices or memory boundaries during cache operations. The vulnerability exists in the core image processing functionality that ImageMagick employs to manage image data in memory, making it particularly dangerous given the library's widespread use across numerous applications and systems. The off-by-one error creates a condition where memory access occurs beyond the allocated buffer boundaries, potentially leading to unpredictable behavior and system instability. This type of vulnerability falls under the CWE-129 weakness category, which specifically addresses improper validation of array indices, and represents a fundamental flaw in memory management practices that can be exploited by malicious actors to disrupt system operations.
The operational impact of this vulnerability extends far beyond simple denial of service conditions, as it can be leveraged by remote attackers to trigger segmentation faults that effectively crash the target system or application. When exploited, the vulnerability allows attackers to send specially crafted image files or data that, when processed by ImageMagick, will cause the application to access memory locations outside of its intended bounds. This results in a segmentation fault that terminates the process and can lead to complete system unavailability, particularly in environments where ImageMagick is used as a core component for image processing. The remote exploitation capability means that attackers do not need physical access to the system, as they can deliver malicious payloads through web applications, file uploads, or any interface that utilizes ImageMagick for image handling. This vulnerability has been categorized under the ATT&CK technique T1499.004 for network denial of service and T1595.001 for reconnaissance through remote services, as it can be used to identify vulnerable systems and disrupt their operations.
The widespread adoption of ImageMagick across various platforms and applications significantly amplifies the potential impact of this vulnerability. Many web applications, content management systems, and image processing tools rely on ImageMagick for their image handling capabilities, making thousands of systems potentially vulnerable to this flaw. The vulnerability's exploitation requires minimal technical expertise, as attackers can simply upload or submit image files that trigger the off-by-one condition without needing to understand complex exploitation techniques. Organizations running services that process user-uploaded images, such as social media platforms, e-commerce sites, and content sharing applications, face particularly high risk from this vulnerability. The memory corruption resulting from the boundary error can also potentially be leveraged for more advanced exploitation techniques if combined with other vulnerabilities, though the primary risk remains focused on denial of service conditions. Security professionals must consider this vulnerability in their threat modeling exercises, particularly in environments where image processing is a critical function and where input validation is not properly implemented at higher application layers.
Mitigation strategies for CVE-2016-7513 should focus on immediate patching of affected ImageMagick installations, as the vulnerability has been addressed through official software updates that correct the boundary condition error. Organizations should implement comprehensive input validation measures at application layers to prevent potentially malicious image files from reaching the ImageMagick processing functions, including file type validation, size restrictions, and content scanning. Network-based mitigations such as intrusion prevention systems and web application firewalls can help detect and block suspicious image file uploads that might trigger the vulnerability. Additionally, organizations should consider implementing sandboxing techniques for image processing operations to limit the potential impact of successful exploitation attempts. Regular vulnerability assessments and security audits should be conducted to identify other potential boundary condition errors in similar image processing libraries and to ensure that all systems utilizing ImageMagick remain up to date with the latest security patches. The vulnerability highlights the importance of rigorous code review processes and automated testing for memory safety issues, particularly in libraries that handle untrusted input data, and serves as a reminder of the critical need for maintaining updated software components in enterprise environments.