CVE-2012-5565 in Groupware
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in js/compose-dimp.js in Horde Internet Mail Program (IMP) before 5.0.24, as used in Horde Groupware Webmail Edition before 4.0.9, allows remote attackers to inject arbitrary web script or HTML via a crafted name for an attached file, related to the dynamic view.
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Analysis
by VulDB Data Team • 05/09/2026
The CVE-2012-5565 vulnerability represents a critical cross-site scripting flaw within the Horde Internet Mail Program IMP component, specifically affecting versions prior to 5.0.24 and Horde Groupware Webmail Edition prior to 4.0.9. This vulnerability resides in the js/compose-dimp.js file and manifests through the dynamic view functionality when processing attached file names. The flaw enables remote attackers to execute malicious web scripts or HTML code within the context of a victim's browser session, creating a significant security risk for email users. The vulnerability exploits the insufficient input sanitization mechanisms that fail to properly escape or validate special characters in file attachment names before rendering them in the web interface. This particular XSS vulnerability falls under the CWE-79 classification as a weakness in input validation and output encoding, where user-controllable data enters a web application and is subsequently rendered back to users without proper sanitization. The attack vector specifically targets the dynamic view feature of the email composition interface, where file attachment names are displayed to users during message composition, making it a prime target for malicious actors seeking to compromise user sessions.
The technical exploitation of this vulnerability occurs when an attacker crafts a malicious file name containing embedded script tags or HTML code and attaches it to an email message. When a victim views this email in the dynamic composition view, the malicious content is executed within their browser context, potentially leading to session hijacking, credential theft, or redirection to malicious websites. The flaw demonstrates poor security practices in web application development where user-provided data is directly incorporated into the page output without proper HTML escaping or context-aware encoding mechanisms. This vulnerability specifically impacts the client-side JavaScript execution environment, leveraging the browser's trust in the application's interface to execute malicious code. The attack scenario involves an attacker sending an email with a specially crafted attachment name that includes malicious JavaScript payload, which executes when the victim opens the email composition view, demonstrating the classic client-side XSS attack pattern. The vulnerability's impact is amplified by the fact that it affects widely deployed email infrastructure components, making it particularly dangerous for enterprise environments where email systems serve as primary communication channels.
The operational impact of CVE-2012-5565 extends beyond simple script execution to potentially enable sophisticated attacks including session fixation, credential harvesting, and phishing operations. Attackers can leverage this vulnerability to steal session cookies, redirect users to malicious domains, or inject malicious content that appears legitimate within the email interface. The vulnerability affects not only individual users but also enterprise email systems that rely on Horde Groupware, potentially compromising large numbers of users simultaneously. Organizations using affected versions face significant risks including data exfiltration, unauthorized access to email accounts, and potential lateral movement within network environments through compromised user credentials. The vulnerability's persistence lies in its ability to remain undetected during normal operation since the malicious code executes only when users view affected email messages. This makes it particularly challenging to monitor and detect, as the attack occurs during normal email usage patterns. The vulnerability's exploitation aligns with ATT&CK technique T1566.001 for initial access through spearphishing with attachments, making it a critical concern for email security and endpoint protection strategies.
Mitigation strategies for CVE-2012-5565 primarily focus on immediate version upgrades to patched releases of Horde IMP and Horde Groupware Webmail Edition, specifically versions 5.0.24 and 4.0.9 respectively. Organizations should implement comprehensive patch management procedures to ensure all affected systems receive timely updates. Additional defensive measures include implementing Content Security Policy (CSP) headers to restrict script execution, deploying web application firewalls to detect and block malicious payloads, and establishing user education programs to recognize suspicious email attachments. Input validation and output encoding should be strengthened throughout the application to prevent similar vulnerabilities, with particular attention to how file names and other user-controllable data are processed and rendered. Regular security assessments and penetration testing should be conducted to identify and remediate similar weaknesses in web application code. The vulnerability serves as a reminder of the critical importance of proper input sanitization and output encoding practices in web development, particularly for applications handling user-generated content in email systems. Organizations should also consider implementing email security gateways that can scan attachments for malicious content and provide additional layers of protection beyond traditional antivirus solutions.