CVE-2007-4442 in Unreal engine
Summary
by MITRE
Stack-based buffer overflow in the logging function in the Unreal engine, possibly 2003 and 2004, as used in the internal web server, allows remote attackers to cause a denial of service (application crash) via a request for a long .gif filename in the images/ directory, related to conversion from Unicode to ASCII.
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Analysis
by VulDB Data Team • 01/22/2025
The vulnerability described in CVE-2007-4442 represents a critical stack-based buffer overflow flaw within the Unreal engine's logging functionality, specifically affecting versions from 2003 and 2004. This issue manifests through the internal web server component when processing requests for image files, particularly those with excessively long .gif filenames located in the images/ directory. The flaw stems from inadequate input validation and memory management within the conversion process from Unicode to ASCII character encoding, creating an exploitable condition that can be remotely triggered by malicious actors. The vulnerability operates at the application layer and specifically targets the engine's internal web server implementation, making it particularly dangerous for systems relying on Unreal engine for web content delivery.
The technical mechanism behind this vulnerability involves a classic stack buffer overflow scenario where the logging function fails to properly validate the length of input data during Unicode to ASCII conversion. When a remote attacker submits a request containing an overly long .gif filename, the system attempts to process this input through the logging function without adequate bounds checking. The conversion process from Unicode to ASCII characters can result in unexpected memory layout changes, causing the buffer to overflow into adjacent stack memory locations. This overflow corrupts the stack frame and can potentially overwrite return addresses or other critical execution data, leading to application instability and crash conditions. The vulnerability falls under CWE-121 Stack-based Buffer Overflow, which is classified as a fundamental memory safety issue in software development practices.
The operational impact of this vulnerability extends beyond simple denial of service conditions to potentially enable more sophisticated attack vectors. While the primary effect manifests as application crashes and service disruption, the underlying buffer overflow condition creates opportunities for attackers to gain unauthorized code execution or escalate privileges within the affected system. Systems utilizing the Unreal engine for web server functionality become particularly vulnerable when exposed to unfiltered user input, as the vulnerability can be exploited through simple HTTP requests without requiring authentication or specialized tools. The attack surface is broadened by the fact that the vulnerability affects multiple versions of the engine, increasing the number of potentially compromised systems. This weakness directly impacts the availability and integrity of web services running on affected platforms, creating potential for business disruption and data accessibility issues.
Mitigation strategies for CVE-2007-4442 should prioritize immediate patching of affected Unreal engine versions, as this represents a fundamental security flaw that cannot be adequately addressed through configuration changes alone. Organizations should implement input validation measures to limit filename lengths and sanitize all user-supplied data before processing, particularly when dealing with image file requests. Network-level protections such as web application firewalls can provide additional defense-in-depth measures by filtering out suspicious requests containing overly long filenames or unusual character sequences. The vulnerability also highlights the importance of proper Unicode handling in software development, emphasizing the need for robust input validation and memory management practices that align with secure coding guidelines. Security monitoring should include detection of unusual file access patterns and potential exploitation attempts targeting the specific images/ directory structure. Organizations should also consider implementing automated vulnerability scanning tools that can identify unpatched systems within their infrastructure, as this vulnerability affects legacy software versions that may not receive regular security updates. The ATT&CK framework categorizes this vulnerability under the T1190 Exploit Public-Facing Application technique, emphasizing the need for comprehensive application security assessments and regular vulnerability management processes to prevent exploitation of similar weaknesses in other system components.