CVE-2015-6122 in Office
Summary
by MITRE
Microsoft Excel 2007 SP3, Excel 2010 SP2, Excel for Mac 2011, Office Compatibility Pack SP3, and Excel Viewer allow remote attackers to execute arbitrary code via a crafted Office document, aka "Microsoft Office Memory Corruption Vulnerability."
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Analysis
by VulDB Data Team • 06/29/2022
The vulnerability identified as CVE-2015-6122 represents a critical memory corruption flaw affecting multiple Microsoft Office versions including Excel 2007 SP3, Excel 2010 SP2, Excel for Mac 2011, Office Compatibility Pack SP3, and Excel Viewer. This vulnerability falls under the category of remote code execution flaws that can be exploited by attackers to gain unauthorized control over affected systems. The flaw stems from improper handling of memory structures when processing specially crafted Office documents, creating opportunities for malicious actors to inject and execute arbitrary code within the target environment. The vulnerability is particularly dangerous because it can be triggered through social engineering attacks where users open maliciously crafted Excel files, making it a significant threat vector in enterprise environments.
The technical nature of this vulnerability involves memory corruption issues that occur during the parsing and rendering of Office document formats. When Microsoft Excel processes malformed or specially crafted Office documents, the application fails to properly validate input data before allocating memory resources. This improper memory management creates buffer overflow conditions or heap corruption scenarios that attackers can manipulate to overwrite critical memory locations. The vulnerability is classified as a memory corruption issue that aligns with CWE-121, which describes heap-based buffer overflow conditions, and potentially CWE-125, which covers out-of-bounds read conditions. These memory corruption flaws typically arise from insufficient bounds checking in memory allocation and deallocation routines within the Office application's document processing engine.
The operational impact of CVE-2015-6122 extends beyond simple remote code execution to encompass significant security implications for organizations relying on Microsoft Office applications. Attackers can leverage this vulnerability to install backdoors, steal sensitive data, deploy additional malware, or establish persistent access to compromised systems. The attack surface is broad since the vulnerability affects multiple Office versions across different platforms, including both Windows and Mac environments. Organizations using these affected versions face elevated risk of targeted attacks where adversaries craft specific Office documents designed to exploit this flaw. The vulnerability can be particularly problematic in environments where users frequently open email attachments or download documents from untrusted sources, as these scenarios provide ideal conditions for exploitation.
Mitigation strategies for CVE-2015-6122 should prioritize immediate patching of affected systems through Microsoft's security updates, as this represents the most effective defense against exploitation. Organizations should implement comprehensive email filtering and attachment scanning solutions to prevent malicious Office documents from reaching end users. Network segmentation and application whitelisting can further reduce the attack surface by limiting user access to potentially vulnerable Office applications. Security teams should also consider disabling macros in Office documents as an additional protective measure, though this approach may impact legitimate business functionality. The vulnerability's classification under the ATT&CK framework would place it within the initial access and execution domains, specifically targeting the use of Office applications for malicious code delivery. Regular security assessments and vulnerability scanning should be conducted to identify and remediate similar memory corruption vulnerabilities across the enterprise environment.