CVE-2014-5248 in MyBB
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in MyBB before 1.6.15 allows remote attackers to inject arbitrary web script or HTML via vectors related to video MyCode.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 02/10/2022
The vulnerability identified as CVE-2014-5248 represents a critical cross-site scripting flaw affecting MyBB versions prior to 1.6.15. This vulnerability resides within the forum software's handling of video MyCode elements, which are used to embed multimedia content within posts. The flaw allows remote attackers to execute malicious scripts in the context of other users' browsers, potentially leading to unauthorized actions on behalf of victims. The vulnerability specifically manifests when the application processes video MyCode tags without proper sanitization of user input, creating an attack surface where malicious actors can inject harmful JavaScript code or HTML content.
The technical exploitation of this vulnerability occurs through the manipulation of video MyCode syntax which is commonly used in forum environments to embed videos from various platforms. When users view posts containing specially crafted video MyCode tags, the malicious code executes in their browsers, potentially stealing session cookies, redirecting users to malicious sites, or performing actions on their behalf. This type of vulnerability falls under CWE-79 which specifically addresses cross-site scripting flaws in web applications. The attack vector involves crafting video MyCode elements that contain embedded JavaScript or HTML payloads, which are then rendered when other users browse the affected forum content.
The operational impact of this vulnerability extends beyond simple script execution, as it enables attackers to perform session hijacking, defacement of forum content, and potential data exfiltration from authenticated users. Forum administrators and users with elevated privileges become particularly vulnerable, as attackers could exploit this flaw to escalate privileges or access sensitive administrative functions. The vulnerability's persistence in forum environments means that once exploited, malicious code can affect all users who view the compromised content, creating a widespread impact across the entire community. This aligns with ATT&CK technique T1566 which covers social engineering tactics involving malicious content delivery.
Mitigation strategies for this vulnerability require immediate patching to MyBB version 1.6.15 or later, which includes proper input sanitization for video MyCode elements. Administrators should implement comprehensive content filtering mechanisms and regularly audit forum posts for suspicious MyCode usage. Additionally, implementing proper output encoding for all user-generated content, including video MyCode, helps prevent script execution in browser contexts. The vulnerability demonstrates the critical importance of validating and sanitizing all user input in web applications, particularly in forum software where users frequently submit multimedia content. Organizations should establish regular security update procedures and maintain awareness of known vulnerabilities in their web applications to prevent similar issues from compromising user security and data integrity.