CVE-2018-9135 in ImageMagick
Summary
by MITRE
In ImageMagick 7.0.7-24 Q16, there is a heap-based buffer over-read in IsWEBPImageLossless in coders/webp.c.
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Analysis
by VulDB Data Team • 02/24/2023
The vulnerability identified as CVE-2018-9135 represents a critical heap-based buffer over-read flaw within ImageMagick's WEBP image format handling component. This issue specifically affects ImageMagick version 7.0.7-24 Q16 and stems from improper bounds checking during the processing of WEBP image files. The vulnerability manifests in the IsWEBPImageLossless function located within the coders/webp.c source file, where insufficient validation allows maliciously crafted WEBP files to trigger memory access violations that could potentially lead to arbitrary code execution or system compromise.
The technical nature of this vulnerability places it squarely within the realm of memory safety issues, specifically categorized under CWE-125 as "Out-of-bounds Read" and potentially related to CWE-787 "Out-of-bounds Write" when considering the broader implications of heap corruption. The flaw occurs when ImageMagick attempts to parse WEBP image metadata and encounters malformed or specially crafted input that exceeds expected buffer boundaries. This over-read condition can cause the application to access memory locations beyond the allocated buffer, potentially exposing sensitive data or creating opportunities for attackers to manipulate program execution flow.
From an operational standpoint, this vulnerability poses significant risks to systems that process untrusted image files, particularly web applications, content management systems, and file upload handlers that utilize ImageMagick for image processing. The attack surface expands considerably when considering that WEBP format support is widely implemented across various platforms and applications, making this flaw exploitable through multiple vectors including web-based file uploads, automated image processing pipelines, and email attachment handling systems. The vulnerability's impact is amplified by the fact that it can be triggered through simple file processing operations without requiring complex exploitation techniques.
The mitigation strategies for CVE-2018-9135 should prioritize immediate patching of affected ImageMagick installations to version 7.0.7-25 or later, which contains the necessary fixes for the buffer over-read condition. Organizations should also implement robust input validation and sanitization measures for all image file processing workflows, including MIME type checking, file size limitations, and content inspection before processing. Additionally, deployment of network-based intrusion detection systems and application firewalls can provide additional layers of protection by monitoring for suspicious file processing patterns. The vulnerability's classification under ATT&CK technique T1059.007 for "Command and Scripting Interpreter: PowerShell" and T1203 for "Exploitation for Client Execution" highlights the need for comprehensive endpoint protection measures and regular security assessments to prevent exploitation through automated attack frameworks.