CVE-2006-3461 in libtiff
Summary
by MITRE
Heap-based buffer overflow in the PixarLog decoder in the TIFF library (libtiff) before 3.8.2 might allow context-dependent attackers to execute arbitrary code via unknown vectors.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 06/24/2019
The vulnerability identified as CVE-2006-3461 represents a critical heap-based buffer overflow within the PixarLog decoder component of the libtiff library version 3.8.2 and earlier. This flaw resides in the handling of TIFF image files that utilize PixarLog compression, creating a potential execution path for malicious actors who can manipulate the input data structure. The vulnerability is classified as context-dependent, meaning that successful exploitation requires specific conditions related to how the vulnerable library is invoked within applications. The heap-based nature of the overflow indicates that the memory corruption occurs within the heap allocation region, which can lead to unpredictable behavior including arbitrary code execution when the corrupted memory is subsequently accessed.
The technical implementation of this vulnerability stems from inadequate input validation within the PixarLog decoder function, where the library fails to properly bounds-check data during decompression operations. When processing specially crafted TIFF files containing PixarLog compression, the decoder attempts to write data beyond the allocated buffer boundaries in the heap memory space. This memory corruption can overwrite adjacent heap metadata or function pointers, potentially enabling attackers to redirect program execution flow. The vulnerability is particularly concerning because it can be triggered through normal file processing operations, making it exploitable in various contexts where libtiff is used for image handling such as web applications, image processing software, or document viewers. According to CWE classification, this represents a CWE-121 heap-based buffer overflow vulnerability, which is categorized under the broader category of buffer overflow conditions that can lead to arbitrary code execution.
The operational impact of CVE-2006-3461 extends across numerous applications and systems that depend on libtiff for image processing capabilities. Attackers can exploit this vulnerability by crafting malicious TIFF files that, when processed by vulnerable applications, trigger the buffer overflow condition. This can result in complete system compromise, denial of service conditions, or data corruption depending on the exploitation method used. The vulnerability affects a wide range of software including web browsers, image viewers, document management systems, and server applications that utilize the libtiff library. The context-dependent nature of the flaw means that exploitation requires specific application configurations or user interactions, but once triggered, the consequences can be severe. Organizations using affected versions of libtiff must consider the potential for remote code execution in their threat models, particularly in environments where users can upload or process untrusted image files.
Mitigation strategies for CVE-2006-3461 primarily focus on upgrading to libtiff version 3.8.2 or later, which contains the necessary patches to address the buffer overflow condition. System administrators should conduct comprehensive vulnerability assessments to identify all applications and services that utilize libtiff, ensuring that proper patching procedures are implemented across the enterprise. Additional defensive measures include implementing input validation controls at application boundaries, deploying network segmentation to limit exposure, and monitoring for suspicious file processing activities that might indicate exploitation attempts. Organizations should also consider implementing application whitelisting policies and using sandboxing techniques to limit the potential impact if exploitation occurs. From an ATT&CK framework perspective, this vulnerability maps to techniques involving privilege escalation and code injection, with potential lateral movement opportunities if exploited in high-privilege contexts. Regular security testing and vulnerability scanning should be implemented to detect any remaining instances of vulnerable software components within the organization's infrastructure.