CVE-2006-4391 in Mac OS X
Summary
by MITRE
Buffer overflow in Apple ImageIO on Apple Mac OS X 10.4 through 10.4.7 allows remote attackers to execute arbitrary code via a malformed JPEG2000 image.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 04/23/2026
The vulnerability identified as CVE-2006-4391 represents a critical buffer overflow flaw within Apple's ImageIO framework, which is a core component of Mac OS X operating systems ranging from version 10.4 through 10.4.7. This issue specifically affects the processing of JPEG2000 image format files, making it particularly dangerous as JPEG2000 is a widely supported image standard that could be encountered in various digital media contexts. The vulnerability stems from inadequate input validation within the image parsing routines that handle JPEG2000 file structures, allowing attackers to craft malicious image files that trigger memory corruption during the decoding process.
The technical implementation of this buffer overflow occurs when the ImageIO framework processes malformed JPEG2000 files without proper bounds checking on array allocations and memory operations. When a specially crafted JPEG2000 image is loaded by an application utilizing ImageIO, the parsing code fails to validate the size parameters within the image file headers, leading to writes beyond allocated memory buffers. This memory corruption can be exploited to overwrite critical program execution data such as return addresses on the stack, enabling attackers to redirect program flow to execute malicious code injected into the memory space. The vulnerability maps directly to CWE-121, which describes heap-based buffer overflow conditions, and specifically aligns with CWE-125, describing out-of-bounds read conditions that can lead to memory corruption.
The operational impact of this vulnerability extends beyond simple code execution as it provides attackers with a remote code execution capability that can be leveraged through various attack vectors including email attachments, web downloads, or malicious websites. Applications that utilize ImageIO for image processing, including Safari web browser, Preview application, and numerous third-party software packages, become potential attack surfaces for this exploit. The remote nature of the attack means that adversaries can deliver malicious JPEG2000 files through standard internet channels without requiring physical access to target systems, making this vulnerability particularly dangerous in enterprise environments where users frequently access untrusted web content or receive email attachments. This vulnerability directly maps to ATT&CK technique T1203, which describes exploitation for execution through malicious file attachments, and T1059, describing command and scripting interpreter usage for code execution.
Mitigation strategies for CVE-2006-4391 involve immediate patching of affected Mac OS X systems through Apple's security updates, which typically include memory boundary checks and improved input validation in the ImageIO framework. System administrators should implement network-based security controls such as content filtering and web proxies that can scan and block JPEG2000 files from untrusted sources. Additionally, users should be educated about the risks of opening image files from unknown sources and should avoid downloading or opening attachments from suspicious email messages. The vulnerability also highlights the importance of regular security updates and the need for application developers to implement proper input validation and memory management practices. Organizations should consider implementing application whitelisting policies that restrict execution of image processing applications to trusted sources only, and should monitor for any suspicious image file handling activities within their networks. The remediation process should include comprehensive testing of patched systems to ensure that the vulnerability is fully resolved without introducing compatibility issues with legitimate image processing operations.