CVE-2017-14865 in Exiv2
Summary
by MITRE
There is a heap-based buffer overflow in the Exiv2::us2Data function of types.cpp in Exiv2 0.26. A Crafted input will lead to a denial of service attack.
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Analysis
by VulDB Data Team • 11/20/2019
The heap-based buffer overflow vulnerability identified as CVE-2017-14865 resides within the Exiv2 image metadata processing library version 0.26, specifically within the Exiv2::us2Data function located in the types.cpp source file. This flaw represents a critical security weakness that manifests when the library processes malformed or crafted input data, potentially leading to system instability and denial of service conditions. The vulnerability is classified under CWE-121 as a stack-based buffer overflow, though the heap-based nature indicates memory corruption occurs in the heap memory region rather than traditional stack allocations. The Exiv2 library serves as a widely-used component for reading and writing image metadata across numerous applications and systems, making this vulnerability particularly concerning for software ecosystems that depend on proper metadata handling.
The technical implementation of this vulnerability stems from inadequate input validation within the Exiv2::us2Data function which processes unsigned 16-bit data values during metadata parsing operations. When maliciously crafted input data is passed to this function, the library fails to properly bounds-check array accesses or validate data lengths before performing memory operations. This lack of proper input sanitization allows an attacker to supply data that exceeds the allocated buffer boundaries, resulting in memory corruption that can overwrite adjacent heap memory locations. The heap-based nature of the overflow means that the corrupted memory segments may contain critical application state information, pointers, or other structured data that when overwritten can cause unpredictable behavior including application crashes, memory corruption, or potentially more severe exploitation vectors.
The operational impact of CVE-2017-14865 extends beyond simple denial of service conditions, as it creates opportunities for more sophisticated attack scenarios within software environments that utilize Exiv2. Applications leveraging this library for image processing, metadata extraction, or file validation may become vulnerable to service disruption when processing malicious files, particularly in automated processing environments or web applications that handle user-uploaded content. The vulnerability's exploitation potential aligns with ATT&CK technique T1203 - Exploitation for Client Execution, as it can be triggered through file processing workflows that are commonly automated or exposed to untrusted input. Systems that process large volumes of images or metadata files become particularly susceptible to this vulnerability, as even a single malicious file can cause application crashes or require system restarts, potentially leading to extended downtime and service degradation.
Mitigation strategies for CVE-2017-14865 should prioritize immediate patching of affected Exiv2 installations to version 0.27 or later, where the buffer overflow vulnerability has been addressed through proper input validation and bounds checking mechanisms. Organizations should implement comprehensive input validation procedures for all image metadata processing workflows, including signature-based detection of malicious file patterns and automated scanning of uploaded content. Network segmentation and access controls should be strengthened to limit exposure of systems that process image metadata, while application-level sandboxing can provide additional protection layers. Security monitoring should be enhanced to detect unusual patterns in image processing operations that may indicate exploitation attempts, and regular vulnerability assessments should be conducted to identify other potential entry points within systems that utilize Exiv2 or similar metadata processing libraries. The vulnerability serves as a reminder of the importance of robust memory management practices and input validation in security-critical software components, particularly those handling untrusted data sources.