CVE-2018-25132 in MyBB Trending Widget Plugin
Summary
by MITRE • 01/23/2026
MyBB Trending Widget Plugin 1.2 contains a cross-site scripting vulnerability that allows attackers to inject malicious scripts through thread titles. Attackers can modify thread titles with script payloads that will execute when other users view the trending widget.
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Analysis
by VulDB Data Team • 01/23/2026
The vulnerability identified as CVE-2018-25132 affects the MyBB Trending Widget Plugin version 1.2, representing a critical cross-site scripting flaw that undermines the security integrity of forum platforms leveraging this plugin. This vulnerability resides within the plugin's handling of thread titles, specifically when these titles are displayed within the trending widget interface. The issue manifests when malicious actors exploit the lack of proper input sanitization to inject script payloads into thread titles, which then execute automatically when other users interact with the trending widget functionality. The attack vector is particularly insidious as it leverages the legitimate display mechanisms of the forum software, making it difficult to distinguish between benign and malicious content at runtime. This vulnerability directly violates the principle of input validation and output encoding, creating an environment where user-generated content can be weaponized to compromise other users' sessions and data.
The technical exploitation of this vulnerability follows the typical XSS attack pattern where the malicious script payload is embedded within thread titles through the plugin's input handling mechanisms. When users browse the forum and encounter the trending widget, the embedded scripts execute in their browser context, potentially stealing session cookies, redirecting users to malicious sites, or performing unauthorized actions on behalf of victims. The vulnerability's impact is amplified by the fact that the trending widget typically displays content prominently and frequently, increasing the attack surface and exposure time for potential victims. The flaw demonstrates inadequate sanitization of user input and failure to properly escape output, which are fundamental security practices that align with CWE-79, the standard classification for cross-site scripting vulnerabilities. This weakness allows attackers to bypass the browser's security model and execute arbitrary code within the victim's browser session, potentially leading to complete account compromise and further lateral movement within the forum environment.
The operational impact of CVE-2018-25132 extends beyond simple script execution, as it provides attackers with a persistent vector for various malicious activities including credential theft, session hijacking, and data exfiltration. Forum administrators face significant risks when this vulnerability exists, as it can be exploited to compromise the entire user base and potentially gain access to sensitive administrative functions. The vulnerability affects not just individual users but the collective security posture of the entire forum community, as compromised users can become unwitting participants in larger attack campaigns. Attackers can craft sophisticated payloads that leverage the trending widget's prominent display position to maximize the effectiveness of their attacks, potentially leading to widespread compromise across the forum platform. The vulnerability's persistence stems from the fact that once malicious content is injected into thread titles, it continues to execute whenever the widget is rendered, creating a continuous threat vector that remains active until the malicious content is removed or the plugin is updated.
Mitigation strategies for this vulnerability must address both immediate remediation and long-term security improvements to prevent similar issues from occurring in the future. The most direct solution involves updating to a patched version of the MyBB Trending Widget Plugin that implements proper input sanitization and output encoding mechanisms. Administrators should also consider implementing content security policies that restrict script execution within the forum environment, providing an additional layer of protection against XSS attacks. Input validation should be strengthened to reject or sanitize any script tags or executable content within thread titles, while output encoding should be enforced when displaying user-generated content in the trending widget. Organizations should also implement regular security audits of third-party plugins and maintain up-to-date vulnerability assessments to identify and remediate similar issues before they can be exploited. The vulnerability's classification under CWE-79 and its alignment with ATT&CK technique T1566.001 for credential access through malicious content emphasizes the importance of comprehensive security measures that address both the immediate threat and systemic weaknesses in input handling processes.