CVE-2018-5246 in ImageMagick
Summary
by MITRE
In ImageMagick 7.0.7-17 Q16, there are memory leaks in ReadPATTERNImage in coders/pattern.c.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 09/12/2024
The vulnerability identified as CVE-2018-5246 affects ImageMagick version 7.0.7-17 within the Q16 build configuration, specifically targeting the memory management functions within the pattern.c source file. This issue manifests as memory leaks during the execution of ReadPATTERNImage function, which is responsible for processing pattern image formats within the broader ImageMagick image processing framework. The memory leak occurs when the application fails to properly release allocated memory resources after processing pattern images, creating a persistent memory consumption issue that can degrade system performance over time. Such vulnerabilities are particularly concerning in image processing applications where multiple files may be processed sequentially, as the cumulative effect of memory leaks can lead to system instability or resource exhaustion.
The technical flaw stems from improper memory deallocation within the ReadPATTERNImage function, where allocated memory blocks are not correctly freed even after the pattern image data has been processed and consumed. This represents a classic memory management error that falls under CWE-401, which specifically addresses memory leaks in software applications. The vulnerability occurs during the image reading process when ImageMagick attempts to parse and interpret pattern format files, and the failure to properly manage memory allocation results in memory blocks remaining in the heap even after their intended use has concluded. The Q16 build configuration indicates that this vulnerability affects the 16-bit quantization implementation of ImageMagick, which is commonly used for high-quality image processing operations.
The operational impact of CVE-2018-5246 extends beyond simple performance degradation, as memory leaks can lead to system resource exhaustion and potentially contribute to denial of service conditions. When applications utilizing ImageMagick process multiple pattern images sequentially, each memory leak contributes to the overall memory consumption, eventually leading to system instability or application crashes. Attackers could potentially exploit this vulnerability by crafting malicious pattern image files that trigger multiple memory leaks during processing, causing cumulative memory consumption that could exhaust system resources. The vulnerability is particularly dangerous in server environments or automated processing systems where ImageMagick may be processing large volumes of images continuously, as the memory leaks can compound over time and eventually render the system unusable.
Mitigation strategies for CVE-2018-5246 should prioritize immediate patching of affected ImageMagick installations to version 7.0.7-18 or later, which contains the necessary memory management fixes. System administrators should implement proper memory monitoring and alerting mechanisms to detect unusual memory consumption patterns that may indicate memory leak occurrences. Additionally, implementing input validation and sanitization measures for pattern image files can help prevent exploitation of memory leak vulnerabilities, particularly in web applications or services that accept user-uploaded images. Organizations should also consider implementing process isolation and resource limits to contain the impact of memory leaks, preventing a single vulnerable process from consuming all available system memory. The vulnerability highlights the importance of proper memory management in image processing libraries and demonstrates how seemingly minor memory leak issues can compound to create significant operational risks in production environments. This aligns with ATT&CK technique T1499.001 which covers resource exhaustion attacks, where attackers exploit memory leaks to exhaust system resources and cause denial of service conditions.