CVE-2007-0544 in MyBB
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in private.php in MyBB (aka MyBulletinBoard) allows remote authenticated users to inject arbitrary web script or HTML via the Subject field, a different vector than CVE-2006-2949.
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Analysis
by VulDB Data Team • 08/18/2018
The vulnerability identified as CVE-2007-0544 represents a cross-site scripting flaw discovered in MyBB version 1.2.4 and earlier, specifically within the private.php script. This issue affects the bulletin board software's handling of user-submitted data in the Subject field of private messages, creating a persistent security weakness that enables malicious actors to execute arbitrary web scripts or HTML content within the context of other users' browsers. The vulnerability operates under the Common Weakness Enumeration classification of CWE-79, which encompasses cross-site scripting flaws, specifically categorized as improper neutralization of input during web output. Unlike CVE-2006-2949 which addressed a similar issue in a different vector, this particular flaw focuses on the Subject field of private messaging functionality, making it a distinct attack surface within the MyBB application's user interface.
The technical implementation of this vulnerability exploits the application's insufficient sanitization of user input when processing private message subjects. When an authenticated user submits a private message with malicious script content in the Subject field, the application fails to properly escape or filter the input before rendering it in the web interface. This allows an attacker to inject HTML tags or JavaScript code that executes when other users view the private message subject. The attack requires the user to be authenticated within the MyBB system, meaning that an attacker must first obtain valid credentials or compromise an existing user account to exploit this vulnerability. The security implications extend beyond simple script execution, as attackers could potentially steal session cookies, redirect users to malicious websites, or perform actions on behalf of victims within the application's context.
The operational impact of CVE-2007-0544 presents significant risks to MyBB community platforms and their users. Attackers could leverage this vulnerability to compromise user sessions, steal sensitive information, or manipulate the bulletin board environment to spread malicious content across multiple users. The authenticated nature of the attack means that even if the application implements basic access controls, malicious users within the community can still exploit this weakness to affect other users. The vulnerability affects the integrity and confidentiality of user communications, potentially allowing attackers to monitor private conversations or inject false information into the system. This type of vulnerability directly impacts the trust model of bulletin board systems where users expect their private communications to remain secure and private. The attack vector specifically targets the Subject field in private messages, making it particularly insidious as users may not immediately recognize the malicious content within what appears to be a legitimate communication subject line.
Mitigation strategies for CVE-2007-0544 involve multiple layers of defensive measures that align with established cybersecurity frameworks and best practices. The primary recommendation is to implement proper input validation and output encoding, ensuring that all user-submitted content undergoes strict sanitization before being rendered in web interfaces. This approach follows the principle of least privilege and input sanitization principles recommended by the Open Web Application Security Project and the Center for Internet Security. System administrators should upgrade to MyBB version 1.2.5 or later, which includes patches specifically addressing this vulnerability. Additionally, implementing Content Security Policy headers can provide an additional layer of protection by restricting the sources from which scripts can be executed. Regular security audits and code reviews should be conducted to identify similar input handling vulnerabilities. The mitigation approach should also include user education about recognizing potentially malicious content in private messages and implementing proper access controls to limit the impact of compromised accounts. Organizations using MyBB should also consider implementing web application firewalls and monitoring systems to detect and prevent exploitation attempts. This vulnerability demonstrates the importance of comprehensive security testing and the need for regular updates to address known vulnerabilities in open-source software platforms.