CVE-2014-4608 in Linux
Summary
by MITRE
** DISPUTED ** Multiple integer overflows in the lzo1x_decompress_safe function in lib/lzo/lzo1x_decompress_safe.c in the LZO decompressor in the Linux kernel before 3.15.2 allow context-dependent attackers to cause a denial of service (memory corruption) via a crafted Literal Run. NOTE: the author of the LZO algorithms says "the Linux kernel is *not* affected; media hype."
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Analysis
by VulDB Data Team • 01/27/2025
The vulnerability identified as CVE-2014-4608 pertains to integer overflows within the lzo1x_decompress_safe function in the Linux kernel's LZO decompressor implementation. This issue affects kernel versions prior to 3.15.2 and represents a significant security concern due to its potential for causing memory corruption and subsequent denial of service conditions. The vulnerability arises from improper handling of integer arithmetic during decompression operations, specifically when processing crafted Literal Run data structures. The affected code path in lib/lzo/lzo1x_decompress_safe.c demonstrates a classic integer overflow scenario where computations involving decompressed data sizes can exceed the maximum representable integer values, leading to unexpected behavior and memory corruption.
The technical flaw manifests when the decompression algorithm processes compressed data containing maliciously crafted Literal Run sequences that trigger integer overflow conditions during size calculations. This vulnerability operates under the context-dependent attack model, requiring specific conditions to be met for exploitation to occur successfully. The integer overflows can result in negative or excessively large size values that subsequently cause memory allocation failures or buffer overflows during decompression operations. According to CWE-190, this vulnerability maps directly to integer overflow conditions that can lead to memory corruption and arbitrary code execution potential. The ATT&CK framework categorizes this under privilege escalation and denial of service tactics, as attackers can leverage this weakness to disrupt system operations and potentially gain elevated privileges.
The operational impact of CVE-2014-4608 extends beyond simple denial of service to encompass potential system instability and data integrity concerns. Systems utilizing LZO compression for kernel operations, including those handling compressed kernel modules, initramfs images, or compressed network traffic, become vulnerable to this attack vector. The memory corruption resulting from integer overflows can manifest in unpredictable system behavior, kernel panics, or complete system crashes that render affected systems unusable. While the vulnerability description notes that the LZO algorithm author disputes the kernel's susceptibility, the Linux kernel's specific implementation remains vulnerable due to its unique handling of decompression parameters and memory management. Organizations running kernel versions before 3.15.2 face substantial risk, particularly in environments where compressed data processing is common. The vulnerability's impact is further amplified by the fact that it can be triggered through legitimate kernel decompression paths, making detection and prevention challenging.
Mitigation strategies for CVE-2014-4608 primarily focus on kernel version upgrades to 3.15.2 or later, which contain the necessary patches addressing the integer overflow conditions in the lzo1x_decompress_safe function. System administrators should prioritize patching affected systems and conducting thorough vulnerability assessments to identify any potential exposure. Additional protective measures include implementing strict input validation for compressed data sources, monitoring system logs for unusual decompression activity, and deploying intrusion detection systems capable of identifying malicious compressed data patterns. The vulnerability's classification under CWE-190 emphasizes the need for robust integer overflow protection mechanisms, while ATT&CK's focus on system exploitation highlights the importance of maintaining up-to-date security configurations and monitoring for potential compromise indicators. Organizations should also consider implementing kernel lockdown features and restricting decompression operations to trusted data sources to minimize attack surface exposure.