CVE-2018-0802 in Office
Summary
by MITRE
Equation Editor in Microsoft Office 2007, Microsoft Office 2010, Microsoft Office 2013, and Microsoft Office 2016 allow a remote code execution vulnerability due to the way objects are handled in memory, aka "Microsoft Office Memory Corruption Vulnerability". This CVE is unique from CVE-2018-0797 and CVE-2018-0812.
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Analysis
by VulDB Data Team • 09/09/2024
The vulnerability identified as CVE-2018-0802 represents a critical memory corruption flaw within Microsoft Office's Equation Editor component affecting multiple versions including Office 2007, 2010, 2013, and 2016. This vulnerability falls under the CWE-125 vulnerability type, which specifically addresses out-of-bounds read conditions that can lead to memory corruption. The flaw manifests when the Equation Editor processes specially crafted objects within Office documents, creating a scenario where memory handling becomes compromised during object manipulation and rendering operations. Attackers can exploit this vulnerability by embedding malicious content within Office documents that, when opened, trigger the vulnerable code path in the Equation Editor component.
The technical exploitation of this vulnerability occurs through memory corruption techniques that leverage improper handling of object references and memory allocation within the Equation Editor's processing pipeline. When a user opens a malicious document containing crafted Equation objects, the Office application attempts to render these objects in memory, but due to insufficient bounds checking and memory management controls, attackers can manipulate the memory layout to execute arbitrary code. This vulnerability is particularly concerning because it operates at the memory level, allowing attackers to potentially bypass modern security mitigations such as DEP, ASLR, and stack canaries. The attack vector requires user interaction through opening a malicious document, making it a typical example of a user-initiated remote code execution vulnerability.
The operational impact of CVE-2018-0802 extends beyond simple code execution, as it provides attackers with a persistent foothold within targeted environments. The vulnerability's presence in multiple Office versions creates widespread exposure across enterprise networks where legacy systems remain operational, particularly in environments where patch management processes are delayed or incomplete. Organizations using these affected Office versions face significant risk of targeted attacks, especially in sectors where Office documents are frequently exchanged and opened by multiple users. The vulnerability's classification as a remote code execution flaw means that attackers can potentially compromise entire systems without requiring physical access or local credentials, making it a particularly attractive target for advanced persistent threat actors. Security researchers have noted that this vulnerability can be combined with other exploitation techniques to create more sophisticated attack chains.
Mitigation strategies for CVE-2018-0802 should prioritize immediate patching of affected Office versions through Microsoft's security updates, as this represents the most effective defense against exploitation. Organizations should implement strict document handling policies that restrict opening of untrusted Office documents, particularly those received via email or downloaded from unknown sources. Network-based security controls including email filtering and web proxies can help prevent the delivery of malicious documents to end users. Additionally, implementing application whitelisting controls can prevent execution of vulnerable Office components when users inadvertently open malicious documents. The ATT&CK framework categorizes this vulnerability under the T1203 technique for Exploitation for Client Execution, highlighting the need for layered security approaches that include endpoint detection and response capabilities. Organizations should also consider disabling the Equation Editor component entirely in environments where it is not required, as this removes the attack surface entirely. Regular security assessments and vulnerability scanning should be implemented to identify any remaining instances of affected Office versions within the organization's infrastructure.