CVE-2017-7597 in LibTIFF
Summary
by MITRE
tif_dirread.c in LibTIFF 4.0.7 has an "outside the range of representable values of type float" undefined behavior issue, which might allow remote attackers to cause a denial of service (application crash) or possibly have unspecified other impact via a crafted image.
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Analysis
by VulDB Data Team • 11/28/2022
The vulnerability identified as CVE-2017-7597 resides within the LibTIFF library version 4.0.7, specifically in the tif_dirread.c component responsible for reading image directory information. This issue represents a critical undefined behavior flaw that stems from improper handling of floating-point values during the parsing of TIFF image files. The vulnerability manifests when the library attempts to process crafted image data that contains values outside the range of representable values for the float data type, creating a scenario where the application's behavior becomes unpredictable and potentially exploitable.
The technical flaw occurs during the TIFF file parsing process where the library encounters image metadata or pixel data that contains floating-point values exceeding the limits of standard float representation. According to CWE-704, this constitutes a weakness in which undefined behavior is introduced through improper data type handling, specifically involving floating-point arithmetic. The vulnerability is particularly concerning because it can be triggered through remote exploitation via crafted TIFF image files, making it suitable for denial-of-service attacks and potentially more severe impacts. When the library encounters these malformed values, the undefined behavior can lead to memory corruption, application crashes, or unpredictable execution paths that may be leveraged by attackers to execute arbitrary code.
From an operational impact perspective, this vulnerability affects any system that processes TIFF images through the affected LibTIFF library version, including image processing servers, document management systems, and applications that handle raster graphics. The potential for remote code execution, while not explicitly confirmed in the original report, remains a significant concern given that undefined behavior in memory handling can often be exploited for more severe attacks. The vulnerability aligns with ATT&CK technique T1203, which involves the use of malicious files to cause system instability or enable privilege escalation. Organizations running web applications, content management systems, or any service that accepts user-uploaded images are particularly vulnerable to this issue, as attackers can craft malicious TIFF files to trigger the crash condition and potentially disrupt services or gain unauthorized access to systems.
Mitigation strategies for CVE-2017-7597 should include immediate patching of the LibTIFF library to version 4.0.8 or later, which contains the necessary fixes for the undefined behavior issue. System administrators should also implement input validation and sanitization measures for all TIFF image processing workflows, including the use of file type checking and size limitations for uploaded images. Network segmentation and application firewalls can help reduce the attack surface by limiting access to systems that process TIFF files. Additionally, implementing robust error handling and memory protection mechanisms within applications that utilize LibTIFF can help prevent exploitation attempts from succeeding. Regular security assessments and vulnerability scanning should be conducted to identify systems running vulnerable versions of the library, with priority given to high-risk environments such as public-facing web applications and enterprise document processing systems. The fix addresses the core issue by implementing proper bounds checking and validation of floating-point values during TIFF directory reading operations, ensuring that all numeric values are within acceptable ranges before processing.