CVE-2019-0870 in Azure DevOps Server
Summary
by MITRE
A Cross-site Scripting (XSS) vulnerability exists when Azure DevOps Server and Team Foundation Server do not properly sanitize user provided input, aka 'Azure DevOps Server and Team Foundation Server Cross-site Scripting Vulnerability'. This CVE ID is unique from CVE-2019-0866, CVE-2019-0867, CVE-2019-0868, CVE-2019-0871.
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Analysis
by VulDB Data Team • 08/28/2023
The vulnerability described in CVE-2019-0870 represents a critical cross-site scripting weakness affecting Azure DevOps Server and Team Foundation Server versions prior to the security patches released in 2019. This flaw resides in the applications' failure to adequately sanitize user-provided input before processing and rendering it within web interfaces, creating an exploitable condition that allows malicious actors to inject arbitrary script code into web pages viewed by other users. The vulnerability specifically impacts the web-based user interfaces of these Microsoft server products, which are widely used for software development lifecycle management, source code control, and project tracking within enterprise environments. The issue stems from insufficient input validation mechanisms that should have filtered out potentially dangerous characters and script sequences before they are processed by the application's rendering engines.
The technical exploitation of this vulnerability occurs when an attacker can manipulate input fields or parameters that are subsequently displayed in web pages without proper sanitization. This allows attackers to inject malicious javascript payloads that execute in the context of other users' browsers, potentially leading to session hijacking, credential theft, or unauthorized access to sensitive project data. The vulnerability is classified under CWE-79 as Improper Neutralization of Input During Web Page Generation, which is a fundamental weakness in web application security that directly enables XSS attacks. Attackers can leverage this flaw by crafting malicious input that includes script tags, event handlers, or other javascript constructs that will be executed when legitimate users view affected pages or interact with the vulnerable application components. The attack typically requires no special privileges beyond normal user access to the affected systems.
The operational impact of CVE-2019-0870 extends beyond simple script execution as it can compromise entire development environments where Azure DevOps Server and Team Foundation Server are deployed. Organizations using these platforms may experience unauthorized access to source code repositories, project management data, build artifacts, and user credentials stored within the systems. The vulnerability particularly threatens environments where developers and team members have elevated privileges, as successful exploitation could lead to complete compromise of development workflows and access to sensitive intellectual property. Given the widespread adoption of these Microsoft server products in enterprise development environments, the potential for cascading security incidents exists, especially when these systems integrate with other corporate infrastructure components. The vulnerability also aligns with ATT&CK technique T1566.001 for Initial Access through Web Application Exploitation, making it a significant vector for broader attack chains within compromised networks.
Mitigation strategies for CVE-2019-0870 focus primarily on applying the official security patches released by Microsoft as part of their regular update cycle. Organizations should immediately deploy the relevant updates to all affected Azure DevOps Server and Team Foundation Server installations, ensuring that all components are properly updated to prevent exploitation. Additionally, implementing robust input validation mechanisms at multiple layers of the application architecture can provide defense-in-depth protection against similar vulnerabilities. Web application firewalls and content security policies should be configured to block suspicious script content, while regular security assessments should be conducted to identify and remediate other potential injection vulnerabilities. Network segmentation and principle of least privilege access controls can limit the potential impact if exploitation occurs, while monitoring systems should be deployed to detect anomalous user behavior patterns that might indicate exploitation attempts. Organizations should also consider implementing automated patch management processes to ensure timely deployment of security updates and maintain comprehensive backup and recovery procedures to address potential compromise scenarios.