CVE-2008-3760 in Vanilla
Summary
by MITRE
Cross-site request forgery (CSRF) vulnerability in the sign-out page in Vanilla 1.1.4 and earlier allows remote attackers to hijack the authentication of arbitrary users for requests that trigger a logout via a SignOutNow action to people.php.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 10/07/2018
The vulnerability described in CVE-2008-3760 represents a critical cross-site request forgery flaw affecting Vanilla forums version 1.1.4 and earlier. This vulnerability specifically targets the sign-out functionality of the web application, creating a dangerous attack vector that enables remote adversaries to manipulate user sessions without authentication. The flaw exists within the people.php script where the SignOutNow action is processed, making it possible for attackers to craft malicious requests that appear legitimate to the vulnerable application. The vulnerability stems from the absence of proper anti-CSRF protection mechanisms in the logout process, which is a fundamental security control that should prevent unauthorized session termination. According to CWE-352, this vulnerability maps directly to Cross-Site Request Forgery, a well-documented weakness that occurs when a web application fails to validate the origin of requests, allowing attackers to perform actions on behalf of authenticated users.
The technical implementation of this vulnerability exploits the trust relationship between the web application and its users. When a user accesses the sign-out page or performs a logout action, the application should verify that the request originates from the legitimate user and not from a malicious third party. However, in Vanilla versions prior to 1.1.5, this validation mechanism was absent or insufficient, allowing attackers to construct specially crafted web pages or links that would automatically trigger logout actions on behalf of authenticated users. The attack typically involves embedding malicious code in a webpage that, when loaded by an authenticated user, automatically submits a request to the people.php script with the SignOutNow action. This creates a scenario where users may be logged out without their knowledge or consent, potentially disrupting their session or even allowing attackers to gain further access to the system through subsequent authentication attempts.
The operational impact of this CSRF vulnerability extends beyond simple session disruption, as it can be leveraged as a stepping stone for more sophisticated attacks within the application ecosystem. The vulnerability affects the core authentication and session management functionality of Vanilla forums, which are essential components for maintaining user privacy and system integrity. Attackers could potentially use this vulnerability to force users into logging out of their accounts, making them temporarily unable to access their forum content or participate in discussions. More concerning is the potential for chaining this vulnerability with other attacks, as demonstrated in the ATT&CK framework where CSRF can be used to facilitate session hijacking or account takeover scenarios. The vulnerability also impacts user trust in the application's security and can lead to reputational damage for forum administrators who fail to address such critical flaws in their software stack.
Mitigation strategies for this vulnerability should focus on implementing robust anti-CSRF protection mechanisms within the web application's authentication flow. The most effective approach involves implementing unique, unpredictable tokens that are generated for each user session and validated on every state-changing request, particularly those involving logout functionality. According to industry best practices, developers should employ the double-submit cookie pattern or use synchronizer tokens to ensure that requests originate from legitimate users. The fix for this specific vulnerability would require updating Vanilla forums to version 1.1.5 or later, where proper CSRF protection has been implemented for the sign-out process. Additionally, administrators should conduct regular security audits of their web applications to identify and remediate similar vulnerabilities, as CSRF attacks continue to be a prevalent threat vector in web application security. Organizations should also implement comprehensive security training for developers to prevent the introduction of such vulnerabilities during the software development lifecycle, ensuring that session management and authentication flows are properly secured against cross-site request forgery attacks.