CVE-2025-7786 in Gnuboard
Summary
by MITRE • 07/18/2025
A vulnerability, which was classified as problematic, has been found in Gnuboard g6 up to 6.0.10. This issue affects some unknown processing of the file /bbs/scrap_popin_update/qa/ of the component Post Reply Handler. The manipulation leads to cross site scripting. The attack may be initiated remotely. The exploit has been disclosed to the public and may be used.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 09/04/2025
The vulnerability identified as CVE-2025-7786 represents a critical cross site scripting flaw within the Gnuboard g6 content management system version 6.0.10 and earlier. This security weakness resides in the post reply handler component, specifically within the file path /bbs/scrap_popin_update/qa/ which processes user input through the web interface. The flaw allows malicious actors to inject arbitrary JavaScript code into the application's response, potentially compromising user sessions and enabling unauthorized actions. The vulnerability's classification as problematic indicates significant security implications that require immediate attention from system administrators and security teams. The affected component handles user interactions in a way that fails to properly sanitize or validate input parameters, creating an avenue for persistent cross site scripting attacks.
The technical exploitation of this vulnerability occurs through the manipulation of parameters within the post reply handler functionality. When users submit replies or interact with the scrap popin update feature, the application processes these inputs without adequate sanitization measures. This processing chain creates an environment where attacker-controlled data can be executed as JavaScript within the context of other users' browsers. The attack vector is remote, meaning that malicious actors can exploit this weakness without requiring physical access to the target system or local network presence. The public disclosure of the exploit further amplifies the risk, as security researchers and threat actors can readily leverage this knowledge to target vulnerable installations. The vulnerability's nature aligns with CWE-79, which specifically addresses cross site scripting flaws in web applications, and may also map to ATT&CK technique T1566.001 for initial access through malicious web content.
The operational impact of this vulnerability extends beyond simple data theft or session hijacking, as it provides attackers with the capability to perform unauthorized actions on behalf of legitimate users. This includes but is not limited to modifying content, accessing sensitive user data, conducting further attacks against the application's infrastructure, or using compromised user sessions to gain deeper access to the system. The affected Gnuboard g6 installations become potential entry points for broader attacks, particularly in environments where the application serves as a platform for user-generated content or collaborative features. Organizations utilizing this CMS may face reputational damage, regulatory compliance violations, and potential financial losses due to data breaches or service disruptions. The vulnerability's impact is particularly concerning in multi-user environments where administrators and regular users interact through the same application interface, as a single compromised session could enable widespread malicious activity.
Mitigation strategies for CVE-2025-7786 should prioritize immediate remediation through official software updates from the Gnuboard maintainers, as version 6.0.11 or later should contain patches addressing the cross site scripting vulnerability. Organizations should implement comprehensive input validation and output encoding measures to prevent similar issues in other application components. Network-level protections including web application firewalls and content filtering systems can provide additional defense in depth. Security teams should conduct thorough vulnerability assessments of all web applications to identify potential similar flaws in input handling mechanisms. Regular security testing including dynamic application security testing and manual penetration testing should be implemented to detect and remediate cross site scripting vulnerabilities before they can be exploited. The incident should trigger a comprehensive review of all user input processing within the application to ensure that proper sanitization and validation mechanisms are in place across all components. Organizations should also establish incident response procedures to quickly address future vulnerabilities and maintain continuous monitoring of security advisories related to their installed software components.