CVE-2018-5247 in ImageMagick
Summary
by MITRE
In ImageMagick 7.0.7-17 Q16, there are memory leaks in ReadRLAImage in coders/rla.c.
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Analysis
by VulDB Data Team • 09/12/2024
The vulnerability identified as CVE-2018-5247 affects ImageMagick version 7.0.7-17 within the Q16 build configuration, specifically targeting the ReadRLAImage function located in the coders/rla.c source file. This issue represents a memory management flaw that occurs during the processing of RLA (RenderMan Large Array) image format files. The RLA format is commonly used in professional rendering applications and digital content creation workflows where large image datasets are processed. The vulnerability manifests as memory leaks that persist throughout the application execution when handling malformed or specially crafted RLA input files, creating a condition where allocated memory is not properly released back to the system.
The technical root cause of this vulnerability stems from inadequate memory management practices within the ReadRLAImage function, which processes RLA image data structures without properly implementing cleanup routines for allocated memory blocks. When the function encounters certain input patterns or malformed RLA files, it fails to execute proper deallocation sequences, leading to progressive memory consumption that can eventually exhaust available system resources. This memory leak behavior aligns with CWE-401, which specifically addresses improper release of memory resources, and represents a classic example of resource exhaustion vulnerabilities that can be exploited to cause denial of service conditions. The vulnerability is particularly concerning in server environments where ImageMagick might process untrusted user input, as it allows attackers to consume system memory continuously without proper cleanup.
The operational impact of CVE-2018-5247 extends beyond simple resource consumption, as it creates persistent memory leaks that can degrade system performance over time and potentially lead to complete system instability or crash conditions. In web applications or services that utilize ImageMagick for image processing, this vulnerability can be exploited through crafted RLA files uploaded by users, resulting in gradual memory exhaustion that affects the entire application or system. The vulnerability affects the availability aspect of the security triad by creating conditions where legitimate system operations may fail due to resource constraints, and it can be leveraged as part of broader attack strategies that combine multiple memory-related vulnerabilities. From an attacker perspective, this vulnerability aligns with ATT&CK technique T1499.004, which involves resource exhaustion via memory corruption, and represents a straightforward path to achieving denial of service through memory management flaws.
Mitigation strategies for CVE-2018-5247 should focus on immediate patching of affected ImageMagick installations to version 7.0.7-18 or later, which contains the necessary memory management fixes. Organizations should implement input validation and sanitization measures to prevent processing of untrusted RLA files, particularly in web-facing applications where user uploads are involved. Additionally, system monitoring should be enhanced to detect unusual memory consumption patterns that might indicate exploitation attempts. The vulnerability highlights the importance of proper memory management in image processing libraries and underscores the need for comprehensive security testing of file format parsers. System administrators should also consider implementing resource limits and process isolation to contain potential impacts from memory leak exploitation attempts, while security teams should monitor for related vulnerabilities in similar image processing libraries that might present analogous memory management issues.