CVE-2018-8606 in Dynamics 365
Summary
by MITRE
A cross site scripting vulnerability exists when Microsoft Dynamics 365 (on-premises) version 8 does not properly sanitize a specially crafted web request to an affected Dynamics server, aka "Microsoft Dynamics 365 (on-premises) version 8 Cross Site Scripting Vulnerability." This affects Microsoft Dynamics 365. This CVE ID is unique from CVE-2018-8605, CVE-2018-8607, CVE-2018-8608.
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Analysis
by VulDB Data Team • 04/12/2020
The vulnerability described in CVE-2018-8606 represents a critical cross site scripting flaw within Microsoft Dynamics 365 on-premises version 8 deployments. This security weakness arises from inadequate input validation and sanitization mechanisms within the web application layer of the Dynamics 365 platform. The vulnerability specifically manifests when the system fails to properly sanitize user-supplied data contained within crafted web requests, allowing malicious actors to inject malicious scripts into the application's response. This flaw falls under the CWE-79 category of Cross Site Scripting, which is classified as a fundamental web application security weakness that enables attackers to execute arbitrary scripts in the context of other users' browsers. The impact is particularly severe in on-premises deployments where organizations maintain direct control over their Dynamics 365 installations, making them prime targets for sophisticated attack campaigns.
The technical exploitation of this vulnerability occurs when an attacker crafts a malicious web request that contains specially formatted script code within parameters or input fields processed by the Dynamics 365 server. When the server processes this malformed request without proper sanitization, the malicious script becomes embedded in the server's response and subsequently executed within the browser context of legitimate users who access the affected application. This type of attack leverages the trust relationship between the user's browser and the Dynamics 365 application, allowing the malicious code to access session cookies, perform unauthorized actions on behalf of users, and potentially exfiltrate sensitive business data. The vulnerability is particularly dangerous because Dynamics 365 typically handles sensitive customer and business information, making successful exploitation potentially devastating for affected organizations. From an attack framework perspective, this vulnerability aligns with ATT&CK technique T1531 - Run-time Application Packing, as it allows for code injection that can be used to establish persistent access or escalate privileges within the application environment.
The operational impact of CVE-2018-8606 extends beyond simple script execution, as it can enable attackers to perform a wide range of malicious activities including session hijacking, data theft, and privilege escalation within the Dynamics 365 environment. Organizations running on-premises Dynamics 365 deployments are particularly vulnerable because they are responsible for maintaining their own security configurations and updates, unlike cloud-based deployments that receive automatic security patches from Microsoft. The vulnerability affects the core web application functionality of Dynamics 365, which means that successful exploitation could compromise the integrity of customer records, sales data, and other business-critical information stored within the system. Attackers could potentially use this vulnerability to establish a foothold within the organization's customer relationship management infrastructure, which often contains sensitive personal and financial information that would be highly valuable on the black market.
Mitigation strategies for CVE-2018-8606 should focus on immediate patching of affected systems, implementing robust input validation mechanisms, and deploying web application firewalls to detect and block malicious requests. Organizations should ensure that all Dynamics 365 on-premises installations are updated to the latest security patches provided by Microsoft, as the vulnerability was addressed through official security updates released in conjunction with the vulnerability disclosure. Additionally, implementing proper output encoding and content security policies can help prevent script execution even if an attacker manages to inject malicious code. Network segmentation and monitoring solutions should be deployed to detect unusual traffic patterns that might indicate exploitation attempts. The remediation process should also include comprehensive security assessments of the Dynamics 365 environment to identify any additional vulnerabilities that might have been introduced through customizations or third-party integrations. Organizations should also consider implementing multi-factor authentication and role-based access controls to limit the potential damage from successful exploitation, as this vulnerability could enable attackers to gain unauthorized access to sensitive business data within the Dynamics 365 system.