CVE-2016-3619 in tvOS
Summary
by MITRE
The DumpModeEncode function in tif_dumpmode.c in the bmp2tiff tool in LibTIFF 4.0.6 and earlier, when the "-c none" option is used, allows remote attackers to cause a denial of service (buffer over-read) via a crafted BMP image.
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Analysis
by VulDB Data Team • 11/21/2022
The vulnerability identified as CVE-2016-3619 resides within the LibTIFF library's bmp2tiff tool, specifically in the DumpModeEncode function located in tif_dumpmode.c. This flaw manifests when the tool processes BMP images with the "-c none" command-line option, creating a scenario where remote attackers can trigger a buffer over-read condition through carefully crafted malicious input files. The issue represents a classic buffer overflow vulnerability that can be exploited to cause system instability and denial of service conditions.
The technical implementation of this vulnerability stems from inadequate input validation and memory management within the DumpModeEncode function. When processing BMP images with the specified compression option, the function fails to properly bounds-check array accesses, allowing an attacker to provide malformed data that exceeds allocated memory boundaries. This over-read condition occurs because the code assumes certain data structures will maintain expected sizes and formats, but crafted inputs can manipulate these assumptions to access memory regions beyond the intended buffer limits. The vulnerability aligns with CWE-125, which describes out-of-bounds read conditions, and represents a fundamental failure in memory safety controls that can be exploited without requiring elevated privileges.
The operational impact of CVE-2016-3619 extends beyond simple denial of service to potentially compromise system availability and stability. When exploited, the buffer over-read can cause the bmp2tiff tool to crash or behave unpredictably, disrupting legitimate image processing workflows that depend on this library. Systems relying on automated image conversion or processing pipelines may experience cascading failures when encountering malicious BMP files, particularly in environments where batch processing or web-based image handling is common. The vulnerability is particularly concerning in server environments where the bmp2tiff utility might be exposed to untrusted input, as it could be leveraged to create persistent denial of service conditions that degrade service availability.
Mitigation strategies for this vulnerability should focus on immediate patching of affected LibTIFF versions to 4.0.7 or later, where the buffer over-read issue has been addressed through proper bounds checking and input validation. Organizations should also implement input sanitization measures for BMP image processing workflows, including file format validation and size limitations to prevent malicious inputs from reaching the vulnerable code paths. The remediation approach aligns with ATT&CK technique T1499.004, which involves avoiding or mitigating system resource consumption attacks, and should be complemented by network segmentation and access controls to limit exposure of vulnerable systems. Additionally, regular security assessments of image processing pipelines and input validation controls can help identify and remediate similar vulnerabilities before they can be exploited in operational environments.