CVE-2016-9043 in CorelDRAW X8
Summary
by MITRE
An out of bound write vulnerability exists in the EMF parsing functionality of CorelDRAW X8 (CdrGfx - Corel Graphics Engine (64-Bit) - 18.1.0.661). A specially crafted EMF file can cause a vulnerability resulting in potential code execution. An attacker can send the victim a specific EMF file to trigger this vulnerability.
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Analysis
by VulDB Data Team • 03/07/2023
The vulnerability identified as CVE-2016-9043 represents a critical out-of-bounds write flaw within CorelDRAW X8's EMF (Enhanced Metafile) parsing component known as CdrGfx - Corel Graphics Engine. This issue resides in the 64-bit version of the graphics engine responsible for processing EMF files, which are commonly used vector graphics format in Windows environments. The vulnerability stems from inadequate bounds checking during the parsing of EMF file structures, specifically when handling certain metafile records that contain malformed data. When CorelDRAW encounters a specially crafted EMF file with maliciously constructed data fields, the graphics engine fails to validate array boundaries properly, leading to memory corruption that can be exploited for arbitrary code execution.
The technical exploitation of this vulnerability follows a classic buffer overflow pattern where attacker-controlled data flows directly into memory regions without proper validation. The flaw occurs during the parsing of EMF records that define graphical operations, particularly those involving color definitions, transformation matrices, or drawing commands that exceed expected data sizes. When the graphics engine attempts to write data beyond allocated memory boundaries, it can overwrite adjacent memory locations including function pointers, return addresses, or other critical program state information. This memory corruption can be leveraged to redirect program execution flow and ultimately achieve remote code execution on the victim's system. The vulnerability's classification aligns with CWE-121, which describes heap-based buffer overflow conditions, and CWE-787, which addresses out-of-bounds write vulnerabilities in memory management operations.
The operational impact of CVE-2016-9043 extends beyond simple code execution, as it represents a significant threat vector for targeted attacks against creative professionals and businesses using CorelDRAW software. Attackers can craft malicious EMF files and deliver them through various social engineering tactics including email attachments, compromised websites, or malicious file sharing platforms. The vulnerability is particularly dangerous because EMF files are commonly used in professional design workflows, making legitimate file exchange scenarios potential attack vectors. Once successfully exploited, the vulnerability allows attackers to execute arbitrary code with the privileges of the affected user, potentially leading to complete system compromise, data exfiltration, or establishment of persistent backdoors. The attack surface is further expanded by the fact that CorelDRAW is widely used in corporate environments, making organizations vulnerable to supply chain attacks or targeted campaigns against creative departments.
Mitigation strategies for CVE-2016-9043 require both immediate defensive measures and long-term architectural improvements. Organizations should immediately apply vendor patches released by Corel to address the memory validation issues in the CdrGfx engine. Additionally, implementing application whitelisting policies that restrict EMF file processing to trusted sources can significantly reduce risk exposure. Network-based defenses including email filtering and web proxy rules can help prevent malicious EMF files from reaching end users. From a defensive architecture perspective, implementing memory protection mechanisms such as DEP (Data Execution Prevention) and ASLR (Address Space Layout Randomization) can make exploitation more difficult, though these protections are not foolproof against sophisticated attacks. The vulnerability also highlights the importance of input validation and bounds checking in graphics processing libraries, aligning with ATT&CK technique T1059.007 for command and scripting interpreter usage in exploitation contexts. Regular security assessments of graphics processing components and implementation of automated vulnerability scanning for third-party libraries should become standard practice to prevent similar issues in the future.