CVE-2017-7275 in ImageMagick
Summary
by MITRE
The ReadPCXImage function in coders/pcx.c in ImageMagick 7.0.4.9 allows remote attackers to cause a denial of service (attempted large memory allocation and application crash) via a crafted file. NOTE: this vulnerability exists because of an incomplete fix for CVE-2016-8862 and CVE-2016-8866.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 11/22/2022
The vulnerability identified as CVE-2017-7275 represents a critical denial of service weakness within ImageMagick's image processing library, specifically affecting the ReadPCXImage function in the coders/pcx.c module. This flaw manifests when the software processes maliciously crafted pcx image files, leading to excessive memory allocation attempts that ultimately result in application crashes. The vulnerability operates as a remote attack vector, meaning that an unauthenticated attacker can exploit this weakness simply by delivering a specially crafted pcx file to a system running ImageMagick, making it particularly dangerous in web environments where users might unknowingly download or process such files. The issue stems from an incomplete remediation of earlier vulnerabilities, specifically CVE-2016-8862 and CVE-2016-8866, which suggests that the original security patches failed to address all potential attack surfaces within the pcx image parsing functionality.
The technical root cause of this vulnerability lies in inadequate input validation and memory management within the pcx image reader component. When ImageMagick encounters a malformed pcx file, the ReadPCXImage function fails to properly validate the file structure and size parameters before attempting to allocate memory for image data. This insufficient validation allows attackers to craft files that specify impossibly large dimensions or memory requirements, causing the application to attempt allocations that exceed available system resources. The vulnerability demonstrates characteristics consistent with CWE-129, which deals with insufficient input validation, and CWE-770, addressing allocation of resources without limits or throttling. The function's failure to implement proper bounds checking on image dimensions and memory requirements creates a path for attackers to exhaust system resources through carefully constructed input files.
The operational impact of CVE-2017-7275 extends beyond simple application crashes, potentially enabling broader system compromise through denial of service attacks that can disrupt legitimate services. In web applications, this vulnerability can be exploited to crash image processing services, preventing users from uploading or viewing images, effectively rendering the service unavailable. The vulnerability affects systems running ImageMagick 7.0.4.9 and potentially earlier versions, making it relevant to numerous web platforms, content management systems, and image processing applications that rely on this library. Attackers can leverage this weakness to perform distributed denial of service attacks against systems processing pcx images, particularly in environments where automatic image processing occurs upon file upload. The vulnerability also demonstrates characteristics of attack patterns documented in the ATT&CK framework under T1499, which covers network denial of service attacks, and T1059, involving the execution of malicious code through file processing.
Mitigation strategies for CVE-2017-7275 require immediate patching of ImageMagick installations to version 7.0.5.0 or later, which contains the complete fix for this vulnerability. System administrators should also implement input validation measures to restrict file types and sizes accepted by applications using ImageMagick, particularly in web-facing environments where users can upload files. Additional protective measures include implementing memory limits and resource constraints on image processing services, deploying network intrusion detection systems to monitor for suspicious file processing patterns, and conducting regular security assessments of image handling components. Organizations should also consider implementing sandboxing techniques for image processing operations to isolate potential exploitation attempts and limit the impact of successful attacks. The vulnerability serves as a reminder of the importance of comprehensive security testing and proper input validation, particularly in libraries that process untrusted data, as partial fixes can leave systems vulnerable to continued exploitation through alternative attack vectors.