CVE-2011-5090 in grboard
Summary
by MITRE
GR Board (aka grboard) 1.8.6.5 Community Edition does not require authentication for certain database actions, which allows remote attackers to modify or delete data via a request to (1) mod_rewrite.php, (2) comment_write_ok.php, (3) poll/index.php, (4) update/index.php, (5) trackback.php, or (6) an arbitrary poll.php script under theme/.
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Analysis
by VulDB Data Team • 02/17/2019
The vulnerability identified as CVE-2011-5090 affects GR Board version 1.8.6.5 Community Edition, representing a critical authentication bypass flaw that exposes sensitive database operations to unauthenticated remote attackers. This issue stems from the application's failure to implement proper access controls for several key database modification endpoints, creating a pathway for malicious actors to directly manipulate the underlying data without requiring valid credentials. The affected components include mod_rewrite.php, comment_write_ok.php, poll/index.php, update/index.php, trackback.php, and arbitrary poll.php scripts located within the theme directory structure, all of which can be exploited to perform unauthorized data modifications.
The technical implementation of this vulnerability demonstrates a fundamental flaw in the application's security architecture where authentication checks are either completely absent or inadequately enforced for database operations. Attackers can leverage this weakness to execute remote code execution against the database layer, potentially leading to complete system compromise through data manipulation, deletion, or unauthorized modifications. The vulnerability operates at the application layer and can be exploited through HTTP requests targeting the specific PHP scripts mentioned in the CVE description, making it particularly dangerous as it requires no prior authentication credentials to exploit.
From an operational perspective, this vulnerability creates significant risk for organizations deploying GR Board Community Edition, as it allows attackers to gain unauthorized access to database content and modify critical application data. The impact extends beyond simple data corruption to include potential information disclosure, service disruption, and possible escalation to full system compromise. The affected scripts cover various application functionalities including comment management, polling systems, update mechanisms, and trackback processing, providing attackers with multiple vectors for exploitation and persistence within the system. This vulnerability aligns with CWE-287, which addresses improper authentication issues, and represents a classic example of how missing access controls can lead to severe security breaches.
The exploitation of CVE-2011-5090 falls under ATT&CK technique T1190 for exploiting vulnerabilities in web applications, specifically targeting the application layer to achieve unauthorized access. Organizations using this vulnerable software face substantial risk as the attack surface includes not only the database but also the entire application functionality that relies on database integrity. The vulnerability's impact is amplified by the fact that it affects multiple endpoints, increasing the probability of successful exploitation and providing attackers with multiple opportunities to achieve their objectives. Security professionals should note that this vulnerability represents a critical weakness in the application's defense-in-depth strategy, where proper authentication mechanisms should have been implemented across all database interaction points.
Mitigation strategies for this vulnerability should include immediate implementation of authentication controls across all database modification endpoints, proper access control enforcement, and regular security auditing of application components. Organizations should also consider implementing web application firewalls to monitor and block suspicious requests targeting the vulnerable scripts, while ensuring that all database operations require proper authentication and authorization checks. The recommended remediation involves patching the application to version 1.8.6.6 or later, where proper authentication mechanisms have been implemented, and conducting thorough security assessments to identify any other potential authentication bypass vulnerabilities within the application stack. Additionally, implementing network segmentation and monitoring for unauthorized database access attempts can provide additional layers of defense against similar exploitation attempts.