CVE-2018-10801 in LibTIFF
Summary
by MITRE
TIFFClientOpen in tif_unix.c in LibTIFF 3.8.2 has memory leaks, as demonstrated by bmp2tiff.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 02/03/2020
The vulnerability identified as CVE-2018-10801 resides within the LibTIFF library version 3.8.2, specifically within the TIFFClientOpen function located in the tif_unix.c file. This memory leak vulnerability manifests when processing certain TIFF image files through the bmp2tiff utility, creating a persistent security concern that affects systems relying on this widely-used library for image processing. The flaw represents a classic memory management issue where allocated memory resources are not properly released, leading to gradual resource exhaustion over time. The vulnerability impacts the library's ability to handle file operations consistently, particularly when dealing with malformed or specially crafted input files that trigger the problematic code path.
The technical implementation of this vulnerability stems from improper memory deallocation within the TIFFClientOpen function, which is responsible for establishing client connections and managing file operations in the TIFF format processing pipeline. When bmp2tiff encounters certain input parameters or file structures, it invokes TIFFClientOpen with specific flags that cause the function to allocate memory for internal data structures without subsequently freeing this memory. This memory leak occurs during the file parsing and conversion process where the library fails to properly clean up allocated resources, creating a condition where memory consumption grows continuously with each processed file. The issue is particularly concerning because it operates at the core level of the TIFF processing library, making it difficult to predict or prevent through higher-level application security measures.
The operational impact of CVE-2018-10801 extends beyond simple resource consumption, potentially enabling denial of service attacks against systems that rely on LibTIFF for image processing tasks. When exploited through repeated file processing operations, the memory leaks can gradually consume available system resources until the application or system becomes unresponsive. This vulnerability affects various applications that depend on LibTIFF for image conversion, manipulation, and viewing, including graphic design software, document management systems, and web applications that handle TIFF image uploads. The vulnerability's exploitation is relatively straightforward since it only requires processing specific input files through the bmp2tiff utility, making it a potential vector for automated attacks against systems that process untrusted image data.
Mitigation strategies for this vulnerability involve immediate patching of the LibTIFF library to version 4.0.9 or later, which contains the necessary fixes to address the memory leak in TIFFClientOpen. System administrators should conduct comprehensive vulnerability assessments to identify all systems running affected versions of LibTIFF and prioritize patch deployment across critical infrastructure. Additionally, implementing input validation measures and restricting file processing operations can help reduce exposure, though these approaches do not address the root cause. The vulnerability aligns with CWE-401, which specifically addresses memory leaks in software applications, and could be categorized under ATT&CK technique T1499.001 for resource exhaustion attacks. Organizations should also consider deploying monitoring solutions to detect unusual memory consumption patterns that might indicate exploitation attempts, while maintaining updated threat intelligence feeds to track related vulnerabilities in the TIFF processing ecosystem.