CVE-2018-19794 in Grouper
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in UiV2Public.index in Internet2 Grouper 2.2 and 2.3 allows remote attackers to inject arbitrary web script or HTML via the code parameter.
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Analysis
by VulDB Data Team • 04/16/2020
The CVE-2018-19794 vulnerability represents a critical cross-site scripting flaw within the Internet2 Grouper 2.2 and 2.3 web applications. This vulnerability exists in the UiV2Public.index component where the application fails to properly sanitize user input before rendering it in web responses. The specific attack vector involves the code parameter which is processed without adequate validation or encoding mechanisms, allowing malicious actors to inject arbitrary JavaScript code or HTML content that executes in the context of other users' browsers.
This vulnerability falls under the CWE-79 category of Cross-Site Scripting, specifically representing a stored XSS variant where malicious payloads can persist and affect multiple users who access the vulnerable application. The attack occurs when remote attackers manipulate the code parameter through HTTP requests, bypassing the application's input validation controls. The vulnerability is particularly dangerous because it affects the public-facing interface of Grouper, making it accessible to anyone with network connectivity to the application, and potentially allowing attackers to escalate privileges or steal session cookies from authenticated users.
The operational impact of this vulnerability extends beyond simple script execution as it can enable attackers to perform session hijacking, redirect users to malicious sites, or extract sensitive information from the application's user base. In the context of Grouper which is designed for identity and access management, this vulnerability could compromise the entire security framework by allowing attackers to manipulate user permissions or access restricted resources. The vulnerability affects both versions 2.2 and 2.3, indicating a widespread issue within the product line that would require comprehensive patching across all affected installations.
Security mitigations for this vulnerability should include immediate implementation of proper input sanitization and output encoding for all user-supplied parameters, particularly those used in dynamic content rendering. The application should employ Content Security Policy headers to limit script execution and implement proper parameter validation using allowlists rather than blocklists. Organizations should also consider implementing web application firewalls to detect and block malicious payloads targeting this specific vulnerability. The ATT&CK framework categorizes this as a web application attack vector under the T1212 technique for exploitation of web application vulnerabilities, emphasizing the need for regular security assessments and input validation controls. Organizations using Internet2 Grouper should prioritize updating to patched versions and conduct thorough security reviews of their web application configurations to prevent exploitation of this and similar vulnerabilities.