CVE-2015-1866 in Ember.js
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in Ember.js 1.10.x before 1.10.1 and 1.11.x before 1.11.2.
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Analysis
by VulDB Data Team • 11/18/2019
The CVE-2015-1866 vulnerability represents a critical cross-site scripting flaw affecting the Ember.js JavaScript framework, specifically impacting versions 1.10.x prior to 1.10.1 and 1.11.x prior to 1.11.2. This vulnerability resides within the framework's handling of user-provided input during template rendering processes, creating a pathway for malicious actors to inject arbitrary JavaScript code into web applications built with Ember.js. The flaw stems from insufficient sanitization of data passed to the framework's templating engine, which processes user content without adequate validation mechanisms. The vulnerability is classified under CWE-79 as a failure to sanitize input, making it a classic example of client-side script injection that can be exploited across various web applications utilizing the affected Ember.js versions.
The technical exploitation of this vulnerability occurs when applications using Ember.js fail to properly escape or sanitize user-supplied data before rendering it within templates. Attackers can craft malicious input that gets processed through the framework's rendering pipeline, ultimately executing unintended JavaScript code in the context of the victim's browser session. The vulnerability is particularly dangerous because it leverages the legitimate functionality of the Ember.js framework itself, making detection more challenging for security monitoring systems. The XSS vector typically manifests when user data is directly interpolated into templates without proper sanitization, allowing attackers to inject script tags or other malicious payloads that execute when the page renders.
The operational impact of CVE-2015-1866 extends beyond simple data theft or session hijacking, as it can enable complete compromise of user sessions and potentially lead to privilege escalation within affected applications. When exploited successfully, this vulnerability allows attackers to perform actions on behalf of authenticated users, access sensitive information, modify application data, or redirect users to malicious sites. The attack surface is broad as any Ember.js application processing user input through templates could be affected, particularly those implementing user-generated content features, comment systems, or any functionality accepting untrusted input. This vulnerability aligns with ATT&CK technique T1566.001 for initial access through malicious web content, and T1059.007 for execution through script-based payloads, demonstrating the multi-faceted nature of the threat.
Mitigation strategies for CVE-2015-1866 primarily focus on immediate version upgrades to patched Ember.js releases, specifically upgrading to 1.10.1 or 1.11.2 and later versions where the XSS vulnerability has been addressed. Organizations should implement comprehensive input validation and output encoding practices across all Ember.js applications, ensuring that user-supplied data is properly escaped before template rendering. The implementation of Content Security Policy (CSP) headers can provide additional defense-in-depth measures to prevent execution of unauthorized scripts, though this should complement rather than replace proper input sanitization. Security teams should conduct thorough vulnerability assessments of all Ember.js applications in their environment, particularly focusing on template usage patterns and user input handling. Regular security testing including dynamic application security testing (DAST) and static application security testing (SAST) should be implemented to identify similar vulnerabilities in custom Ember.js code and prevent future occurrences of this class of flaw.