CVE-2008-4864 in Python
Summary
by MITRE
Multiple integer overflows in imageop.c in the imageop module in Python 1.5.2 through 2.5.1 allow context-dependent attackers to break out of the Python VM and execute arbitrary code via large integer values in certain arguments to the crop function, leading to a buffer overflow, a different vulnerability than CVE-2007-4965 and CVE-2008-1679.
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Analysis
by VulDB Data Team • 01/14/2025
The vulnerability identified as CVE-2008-4864 represents a critical security flaw in Python's image processing capabilities that existed across versions 1.5.2 through 2.5.1. This issue resides within the imageop module's imageop.c file and specifically targets the crop function implementation. The vulnerability stems from improper handling of integer values that can cause arithmetic overflow conditions when processing large integer arguments, creating a pathway for malicious exploitation that bypasses normal Python virtual machine protections.
The technical implementation of this vulnerability involves integer overflow conditions that occur during buffer size calculations within the crop function of the imageop module. When attackers provide excessively large integer values as parameters to the crop function, these values cause integer arithmetic to exceed the maximum representable value for the data type being used, resulting in wraparound behavior that produces unexpectedly small or negative buffer sizes. This fundamental flaw in input validation and arithmetic handling creates a scenario where the application allocates insufficient memory for buffer operations, leading to memory corruption that can be exploited to execute arbitrary code outside the intended Python execution environment.
The operational impact of CVE-2008-4864 extends beyond simple code execution to represent a complete breakdown of the Python virtual machine's memory protection mechanisms. Attackers can leverage this vulnerability to escape the controlled Python execution environment and gain arbitrary code execution privileges on the underlying system, potentially leading to full system compromise. The vulnerability specifically targets context-dependent scenarios where the imageop module processes user-supplied image data, making it particularly dangerous in web applications or any environment where untrusted image data is processed through Python's image manipulation functions. This issue operates under the broader category of buffer overflow vulnerabilities, which are classified under CWE-121 and CWE-122, and represents a classic example of how integer overflows can lead to memory corruption exploits.
Mitigation strategies for CVE-2008-4864 require immediate version upgrades to Python 2.5.2 or later, where the integer overflow conditions have been properly addressed through enhanced input validation and arithmetic overflow protection mechanisms. Organizations should implement comprehensive input sanitization measures for any image processing functions that utilize the imageop module, particularly focusing on validating parameter ranges before processing. The vulnerability aligns with ATT&CK technique T1059.006 for execution through Python scripts, and organizations should monitor for potential exploitation attempts through automated scanning tools that target known vulnerable Python versions. Additionally, system administrators should consider implementing network segmentation and application whitelisting to limit exposure, as the vulnerability specifically affects applications that process external image data through Python's image manipulation libraries, making it particularly relevant for web applications, content management systems, and image processing services.