CVE-2016-7517 in ImageMagick
Summary
by MITRE
The EncodeImage function in coders/pict.c in ImageMagick allows remote attackers to cause a denial of service (out-of-bounds read) via a crafted PICT file.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 07/04/2024
The vulnerability identified as CVE-2016-7517 resides within the EncodeImage function of ImageMagick's coders/pict.c module, representing a critical security flaw that enables remote attackers to execute denial of service attacks through carefully crafted PICT image files. This vulnerability specifically manifests as an out-of-bounds read condition that occurs when the software processes malformed PICT format data, allowing malicious actors to manipulate the image processing pipeline and potentially crash the application or consume excessive system resources.
The technical nature of this vulnerability aligns with CWE-125, which describes out-of-bounds read conditions where programs access memory locations beyond the bounds of allocated buffers. The flaw occurs during the image encoding process when ImageMagick fails to properly validate the structure and boundaries of PICT format files before attempting to read and process their contents. The EncodeImage function does not adequately check array indices or buffer limits when parsing PICT file headers and data segments, creating opportunities for attackers to craft malicious files that cause the software to read memory locations outside the intended data structures.
From an operational perspective, this vulnerability presents significant risks to systems that utilize ImageMagick for image processing, particularly web applications, content management systems, and any platform that accepts user-uploaded images. The remote exploitation capability means that attackers can trigger the denial of service condition without requiring local access or authentication, making it particularly dangerous in environments where users can upload arbitrary image files. The impact extends beyond simple service disruption as the vulnerability can potentially lead to system instability, resource exhaustion, and in some cases, may provide a foothold for more sophisticated attacks if combined with other vulnerabilities.
The exploitation of this vulnerability follows patterns consistent with ATT&CK technique T1203, which involves using malicious files to cause denial of service conditions. Attackers typically craft PICT files with malformed headers or corrupted data structures that, when processed by ImageMagick, trigger the out-of-bounds read condition. This vulnerability affects a wide range of applications and systems that rely on ImageMagick's image processing capabilities, including but not limited to web applications, file upload systems, and image processing servers. The vulnerability is particularly concerning because ImageMagick is widely deployed across various platforms and applications, amplifying the potential impact of successful exploitation.
Mitigation strategies for CVE-2016-7517 should prioritize immediate patching of affected ImageMagick installations to the latest versions that contain the necessary security fixes. Organizations should also implement input validation and sanitization measures to filter potentially malicious image files before they reach the ImageMagick processing pipeline. Network-based mitigations such as implementing file type restrictions, content scanning, and rate limiting on image upload functionality can help reduce the attack surface. Additionally, system administrators should consider implementing application whitelisting and sandboxing techniques to limit the potential impact of successful exploitation attempts, ensuring that even if an attacker manages to trigger the vulnerability, the damage remains contained within isolated environments.