CVE-2017-11534 in ImageMagick
Summary
by MITRE
When ImageMagick 7.0.6-1 processes a crafted file in convert, it can lead to a Memory Leak in the lite_font_map() function in coders/wmf.c.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 12/13/2022
CVE-2017-11534 represents a memory leak vulnerability within ImageMagick version 7.0.6-1 that specifically affects the convert utility when processing maliciously crafted input files. This vulnerability resides in the lite_font_map() function located within the coders/wmf.c source file, demonstrating a classic memory management flaw that can be exploited through improper resource handling during file processing operations. The issue stems from insufficient memory deallocation mechanisms when parsing Windows Metafile format files, creating a condition where allocated memory segments remain unreleased even after processing completion. This vulnerability falls under CWE-401: Improper Release of Memory and aligns with ATT&CK technique T1059.007 for execution through command-line interfaces where malicious file processing could occur. The memory leak occurs during the conversion process when ImageMagick attempts to map font resources from WMF files, with the lite_font_map() function failing to properly clean up allocated memory structures. Attackers could leverage this vulnerability by crafting specially formatted WMF files that, when processed by convert, cause progressive memory consumption that eventually leads to system performance degradation or complete system resource exhaustion. The impact extends beyond simple memory consumption as this vulnerability can be chained with other memory-related issues to create more severe exploitation vectors. The vulnerability is particularly concerning in server environments where ImageMagick is used for automated file conversion services, as sustained exploitation could lead to denial of service conditions. This flaw represents a critical security gap in the application's resource management protocols and demonstrates the importance of proper memory deallocation practices in multimedia processing applications. The vulnerability's exploitation requires minimal privileges and can be triggered through standard file processing workflows, making it an attractive target for automated attack systems. Security researchers have documented similar patterns in other graphics processing libraries, where insufficient cleanup routines in font mapping functions have led to memory exhaustion attacks. Organizations using ImageMagick in production environments should prioritize patching this vulnerability as it provides a straightforward path to resource exhaustion attacks that can significantly impact system availability and performance. The memory leak behavior specifically affects the WMF file format parser, indicating that the vulnerability is not universal across all supported formats but rather specific to how ImageMagick handles Windows Metafile conversions. This targeted nature suggests that the issue stems from inadequate handling of font resource allocation specifically within the WMF processing pipeline rather than broader memory management failures in the entire ImageMagick codebase. The vulnerability's classification as a memory leak aligns with industry standards for resource management failures and represents a significant concern for applications that process untrusted file inputs, particularly in web applications and file conversion services. Mitigation strategies should include immediate patch application, input validation, and monitoring for unusual memory consumption patterns in systems processing file conversions. The vulnerability also highlights the importance of proper code review and testing of resource management functions, particularly in libraries that handle complex multimedia file formats where font and resource mapping operations are common.