CVE-2018-8587 in Outlook
Summary
by MITRE
A remote code execution vulnerability exists in Microsoft Outlook software when it fails to properly handle objects in memory, aka "Microsoft Outlook Remote Code Execution Vulnerability." This affects Office 365 ProPlus, Microsoft Office, Microsoft Outlook.
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Analysis
by VulDB Data Team • 06/18/2023
The vulnerability identified as CVE-2018-8587 represents a critical remote code execution flaw within Microsoft Outlook software that stems from improper handling of objects in memory. This weakness allows attackers to execute arbitrary code on affected systems when Outlook processes specially crafted malicious objects. The vulnerability specifically impacts Microsoft Outlook versions across multiple product lines including Office 365 ProPlus and various Microsoft Office installations, making it a widespread concern for enterprise environments that rely heavily on email communication platforms. The flaw exists at the memory management level where Outlook fails to properly validate or sanitize object references during processing operations.
The technical exploitation of this vulnerability occurs when Microsoft Outlook encounters malformed or maliciously crafted objects within email messages or attachments. When the application attempts to parse these objects, the improper memory handling causes the application to behave unpredictably, potentially allowing attackers to inject and execute malicious code with the privileges of the user running Outlook. This type of vulnerability falls under CWE-125, which describes "Out-of-bounds Read" conditions that can lead to memory corruption and arbitrary code execution. The vulnerability demonstrates characteristics of heap-based buffer overflows and memory corruption issues that have been historically exploited in email client applications.
From an operational standpoint, this vulnerability poses significant risks to organizations as it can be exploited through standard email delivery mechanisms without requiring user interaction beyond opening a malicious email message. Attackers can craft emails containing specially formatted objects that trigger the memory handling flaw when Outlook processes them, potentially leading to full system compromise. The impact extends beyond individual user devices to enterprise networks where compromised Outlook instances could serve as initial access points for broader attacks. This vulnerability directly aligns with ATT&CK technique T1190, "Exploit Public-Facing Application," and T1059, "Command and Scripting Interpreter," as it enables attackers to execute code remotely through email-based attacks.
Organizations should implement immediate mitigations including applying Microsoft security updates and patches released for this vulnerability, which address the memory handling issues in Outlook's object processing routines. Network segmentation and email filtering solutions should be enhanced to detect and block suspicious email content that might exploit this vulnerability. Additionally, user education regarding suspicious email attachments and the importance of keeping software updated remains crucial. Security teams should monitor for indicators of compromise related to this vulnerability and consider implementing application control measures that restrict Outlook's ability to process untrusted content. The remediation process should prioritize immediate patch deployment followed by comprehensive security assessments of email handling procedures and network defenses.