CVE-2012-1206 in Hancom Office 2010 SE
Summary
by MITRE
Multiple integer overflows in Hancom Office 2010 SE 8.5.5 allow remote attackers to execute arbitrary code via large dimension values in a (1) JPG image to the ImportGR in the JPG image filter module (HncJpeg10.flt) or (2) PNG image to the PNG image filter module (HncPng10.flt), which triggers a heap-based buffer overflow.
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Analysis
by VulDB Data Team • 01/23/2018
The vulnerability identified as CVE-2012-1206 represents a critical security flaw in Hancom Office 2010 SE version 8.5.5 that stems from improper input validation mechanisms within its image processing modules. This vulnerability manifests through integer overflow conditions that occur when the software processes specially crafted image files, specifically JPG and PNG formats, leading to potential remote code execution capabilities for attackers. The flaw exists in the core image filter modules responsible for handling graphic file imports, making it particularly dangerous as it can be exploited through standard document delivery mechanisms.
The technical implementation of this vulnerability involves two distinct attack vectors within the Hancom Office application's image processing pipeline. The first vector targets the ImportGR function within the JPG image filter module HncJpeg10.flt, while the second vector affects the PNG image filter module HncPng10.flt. Both modules fail to properly validate dimension parameters in image files, allowing attackers to craft malicious image files with intentionally large dimension values that cause integer overflows. When these overflow conditions occur, they result in heap-based buffer overflow scenarios where the application attempts to write data beyond the allocated memory boundaries, potentially corrupting adjacent memory regions and enabling arbitrary code execution.
The operational impact of this vulnerability extends beyond simple exploitation as it represents a sophisticated attack surface that can be leveraged through social engineering campaigns or automated scanning systems. Attackers can deliver malicious documents containing specially crafted images that, when opened by vulnerable Hancom Office installations, trigger the integer overflow conditions and subsequently execute malicious code on target systems. This vulnerability aligns with CWE-190, which specifically addresses integer overflow conditions, and demonstrates how improper integer handling can lead to memory corruption vulnerabilities. The attack vector is particularly concerning as it requires no privileged access or special user interaction beyond opening a malicious document, making it suitable for widespread exploitation.
From a threat modeling perspective, this vulnerability maps directly to ATT&CK technique T1203, which involves gaining access to systems through exploitation of software vulnerabilities, and T1059, which covers execution through command and scripting interpreters. The heap-based buffer overflow characteristic makes this vulnerability particularly attractive to attackers as it can be used to overwrite critical program execution pointers or inject shellcode directly into memory. The vulnerability's remote execution capability means that attackers can compromise systems without requiring physical access or direct system interaction, making it a prime target for automated exploitation frameworks. Organizations utilizing Hancom Office 2010 SE should consider immediate mitigation strategies including software updates, network segmentation, and application whitelisting to prevent exploitation of this vulnerability.
The remediation approach for CVE-2012-1206 requires immediate software patching from the vendor, as the vulnerability stems from fundamental flaws in the application's input validation and memory management processes. System administrators should implement comprehensive monitoring for suspicious document opening activities and network traffic patterns that might indicate exploitation attempts. Additionally, organizations should consider implementing network-based intrusion detection systems to identify and block traffic patterns associated with exploitation attempts. The vulnerability demonstrates the critical importance of proper integer overflow protection and buffer size validation in security-critical applications, particularly those handling user-supplied data through image processing pipelines.