CVE-2015-3191 in Cloud Foundry Runtime
Summary
by MITRE
With Cloud Foundry Runtime cf-release versions v209 or earlier, UAA Standalone versions 2.2.6 or earlier and Pivotal Cloud Foundry Runtime 1.4.5 or earlier the change_email form in UAA is vulnerable to a CSRF attack. This allows an attacker to trigger an e-mail change for a user logged into a cloud foundry instance via a malicious link on a attacker controlled site. This vulnerability is applicable only when using the UAA internal user store for authentication. Deployments enabled for integration via SAML or LDAP are not affected.
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Analysis
by VulDB Data Team • 10/03/2020
The vulnerability described in CVE-2015-3191 represents a critical cross-site request forgery flaw within the User Account and Authentication (UAA) component of Pivotal Cloud Foundry deployments. This vulnerability specifically affects Cloud Foundry Runtime cf-release versions 209 and earlier, UAA Standalone versions 2.2.6 and earlier, and Pivotal Cloud Foundry Runtime 1.4.5 and earlier. The flaw resides in the change_email form functionality of the UAA service, which fails to implement proper anti-CSRF protection mechanisms. The vulnerability operates by exploiting the trust relationship between the UAA service and its authenticated users, allowing malicious actors to craft deceptive links that, when clicked by authenticated users, automatically submit email change requests without their explicit consent. This issue falls under CWE-352, which specifically addresses Cross-Site Request Forgery vulnerabilities, and aligns with ATT&CK technique T1566.002 for credential access through social engineering attacks.
The technical implementation of this vulnerability stems from the absence of anti-CSRF tokens in the change_email form submission process. When a user is logged into a Cloud Foundry instance, their session remains active and authenticated with the UAA service. An attacker can construct a malicious webpage containing a hidden form submission that targets the UAA email change endpoint. The form would automatically submit the request using the victim's active session cookies, effectively performing an email address modification without the user's knowledge or consent. The vulnerability is particularly concerning because it directly impacts user account security and could enable further attacks such as account takeover, credential theft, or unauthorized access to sensitive application resources. The attack vector requires the victim to be authenticated with the Cloud Foundry instance and to click on the malicious link, making it a classic example of a user-initiated CSRF attack that leverages session management weaknesses.
The operational impact of CVE-2015-3191 extends beyond simple email address modification, as it fundamentally compromises user authentication integrity within Cloud Foundry environments. An attacker who successfully exploits this vulnerability could redirect user email addresses to attacker-controlled addresses, potentially enabling them to reset passwords through the standard password recovery mechanisms. This creates a significant risk for organizations relying on Cloud Foundry for application deployment and management, particularly those handling sensitive data or mission-critical applications. The vulnerability affects only deployments using the UAA internal user store, meaning that organizations utilizing SAML or LDAP authentication integrations remain unaffected. However, this limitation does not mitigate the risk for affected deployments, as the internal user store is commonly used in many Cloud Foundry installations, especially in development and testing environments where external identity providers are not yet implemented.
Organizations should implement immediate mitigation strategies to address this vulnerability, including upgrading to patched versions of Cloud Foundry Runtime, UAA Standalone, or Pivotal Cloud Foundry Runtime that contain proper CSRF protection mechanisms. The recommended remediation involves ensuring that all form submissions in the UAA service include unique, unpredictable anti-CSRF tokens that are validated server-side before processing any email change requests. Additionally, administrators should review and implement proper session management policies, including session timeout configurations and secure cookie attributes such as HttpOnly and Secure flags. Organizations should also consider implementing network-level protections such as web application firewalls that can detect and block suspicious form submissions. The vulnerability demonstrates the importance of implementing comprehensive security controls throughout the application lifecycle, particularly in authentication and session management components, and aligns with security best practices outlined in NIST SP 800-53 and ISO/IEC 27001 standards for protecting against unauthorized access and maintaining user account integrity.