CVE-2016-9414 in MyBB
Summary
by MITRE
MyBB (aka MyBulletinBoard) before 1.8.7 and MyBB Merge System before 1.8.7 allow remote attackers to obtain sensitive information by leveraging missing directory listing protection in upload directories.
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Analysis
by VulDB Data Team • 08/08/2020
The vulnerability identified as CVE-2016-9414 affects MyBB forums and MyBB Merge System versions prior to 1.8.7, presenting a critical information disclosure risk that stems from inadequate directory protection mechanisms. This flaw enables remote attackers to access sensitive data through improperly configured upload directories that lack proper access controls and directory listing restrictions. The vulnerability represents a fundamental security misconfiguration that undermines the integrity of the application's file upload functionality and exposes potentially sensitive system information to unauthorized users.
The technical implementation of this vulnerability lies in the absence of proper directory listing protection within the application's upload directories. When web servers are configured to allow directory browsing or when proper access controls are not enforced, attackers can traverse to upload directories and enumerate files that should remain protected. This misconfiguration creates an information disclosure channel that allows adversaries to discover file names, directory structures, and potentially sensitive metadata that could reveal system configurations, user data, or application internals. The vulnerability is classified under CWE-540, which specifically addresses the inclusion of sensitive information in source code, and aligns with ATT&CK technique T1213.002 for Data from Information Repositories, as it enables unauthorized access to stored information.
The operational impact of this vulnerability extends beyond simple information disclosure, as the exposed data could provide attackers with valuable intelligence for subsequent attacks. Attackers may discover backup files, configuration files, or temporary uploads that contain database credentials, user session information, or application-specific data that could facilitate privilege escalation or further compromise. The vulnerability affects the confidentiality aspect of the CIA triad, as it allows unauthorized information access without requiring authentication or exploitation of other vulnerabilities. The attack surface is particularly concerning in environments where MyBB forums serve as public-facing platforms with extensive user-generated content and file uploads.
Mitigation strategies for CVE-2016-9414 should focus on implementing proper directory access controls and disabling directory listing functionality on web servers hosting MyBB applications. Administrators should ensure that upload directories are configured to prevent directory browsing and that proper file permissions are enforced to restrict access to authorized users only. The most effective remediation involves upgrading to MyBB version 1.8.7 or later, which includes the necessary security patches to address the directory listing protection gaps. Additionally, implementing web application firewalls and security monitoring solutions can help detect and prevent unauthorized access attempts to sensitive directories. Organizations should also conduct regular security assessments to identify and remediate similar misconfigurations in other web applications and ensure that all upload functionality includes proper access controls and input validation to prevent exploitation of similar vulnerabilities.