CVE-2018-8804 in ImageMagick
Summary
by MITRE
WriteEPTImage in coders/ept.c in ImageMagick 7.0.7-25 Q16 allows remote attackers to cause a denial of service (MagickCore/memory.c double free and application crash) or possibly have unspecified other impact via a crafted file.
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Analysis
by VulDB Data Team • 02/22/2023
The vulnerability identified as CVE-2018-8804 resides within ImageMagick's EPT (Enhanced PostScript) image coder implementation, specifically in the WriteEPTImage function located in coders/ept.c. This flaw affects ImageMagick version 7.0.7-25 Q16 and represents a critical security issue that can be exploited remotely by attackers who craft malicious EPT files. The vulnerability manifests as a double free condition in MagickCore/memory.c, which occurs when the application attempts to release the same memory block twice during the processing of malformed input files. This memory management error directly leads to application crashes and can potentially be leveraged for more severe consequences including arbitrary code execution or information disclosure.
The technical root cause of this vulnerability stems from improper memory deallocation handling within the EPT image processing pipeline. When ImageMagick encounters a crafted EPT file, the WriteEPTImage function fails to properly validate memory allocation patterns, resulting in a scenario where memory pointers are freed multiple times. This double free vulnerability falls under CWE-415, which specifically addresses improper double-free conditions in memory management. The flaw is particularly dangerous because it can be triggered through the standard image processing workflow, making it accessible to attackers who can upload or process malicious files through applications that rely on ImageMagick for image handling operations. The vulnerability demonstrates a classic memory safety issue where the application's resource management logic does not adequately track memory allocations and deallocations.
From an operational perspective, this vulnerability creates significant risk for systems that process untrusted image files, particularly web applications, content management systems, and file processing services that utilize ImageMagick. The denial of service impact can be severe as it can cause legitimate applications to crash repeatedly, leading to service disruption and potential availability issues. Additionally, the unspecified other impacts mentioned in the vulnerability description suggest potential for more serious consequences including privilege escalation or code execution, which would transform this into a remote code execution vulnerability. The attack vector is particularly concerning as it requires no special privileges to exploit and can be delivered through simple file uploads or network-based file processing operations. Organizations using ImageMagick in production environments are at risk of experiencing system instability and potential security breaches if this vulnerability is not addressed.
Mitigation strategies for CVE-2018-8804 should prioritize immediate patching of affected ImageMagick installations to version 7.0.7-26 or later, which contains the necessary fixes for the double free condition. Network-level defenses should include implementing strict file validation and sanitization processes that filter out potentially malicious image files before they reach ImageMagick processing components. Organizations should also consider implementing sandboxing mechanisms around image processing operations to limit the potential impact of exploitation attempts. The vulnerability aligns with ATT&CK technique T1203, which covers Exploitation for Client Execution, and T1499, which addresses Network Denial of Service. System administrators should also monitor for unusual application behavior or crash patterns that might indicate exploitation attempts, and implement proper logging and alerting mechanisms to detect potential abuse of this vulnerability in production environments.