CVE-2004-1443 in IMP
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in the inline MIME viewer in Horde-IMP (Internet Messaging Program) 3.2.4 and earlier, when used with Internet Explorer, allows remote attackers to inject arbitrary web script or HTML via an e-mail message.
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Analysis
by VulDB Data Team • 06/05/2019
The vulnerability identified as CVE-2004-1443 represents a critical cross-site scripting flaw within the Horde-IMP email client software, specifically affecting versions 3.2.4 and earlier. This issue resides in the inline MIME viewer component that processes email content directly within the browser interface. The vulnerability is particularly concerning as it leverages the widespread use of Internet Explorer as a default email client, creating an expansive attack surface where malicious actors can exploit this weakness to execute arbitrary code in the context of the victim's browser session. The flaw fundamentally stems from insufficient input validation and output encoding mechanisms within the email rendering process, allowing attackers to inject malicious scripts that execute when users view compromised email messages.
The technical implementation of this vulnerability involves the improper handling of email content that contains embedded script tags or malicious JavaScript code within MIME attachments or message bodies. When Internet Explorer processes these malformed email messages through the inline viewer, it fails to properly sanitize the content before rendering it in the browser environment. This lack of proper sanitization creates an XSS vector where attackers can craft specially formatted emails containing malicious payloads that execute in the victim's browser context. The vulnerability specifically affects the MIME viewer functionality that attempts to display various email formats inline rather than requiring separate downloads, making it particularly dangerous as users may inadvertently trigger the exploit simply by opening an infected email message.
The operational impact of CVE-2004-1443 extends far beyond simple script execution, as it provides attackers with the capability to perform session hijacking, steal user credentials, redirect users to malicious websites, or execute additional attacks through the compromised browser session. The attack requires minimal user interaction beyond opening the malicious email, making it particularly effective for phishing campaigns or social engineering attacks. This vulnerability directly maps to CWE-79, which defines improper neutralization of input during web output, and aligns with ATT&CK technique T1566.001 for initial access through spearphishing attachments. The exploitability is significantly enhanced by the combination of the vulnerable software version and Internet Explorer's specific rendering behavior, which creates a perfect storm for successful exploitation.
Mitigation strategies for this vulnerability require immediate patching of affected Horde-IMP installations to versions that include proper input sanitization and output encoding mechanisms. Organizations should implement email filtering solutions that scan for suspicious content patterns and disable inline viewing of email attachments where possible. Security configurations should enforce strict content security policies that prevent script execution within email contexts, and user education programs should emphasize the dangers of opening suspicious email messages. Additionally, network-level protections such as web application firewalls and email security gateways can provide additional layers of defense against exploitation attempts. The vulnerability serves as a prime example of why proper input validation and output encoding are critical security controls, particularly in web applications that process untrusted data from external sources, and demonstrates the importance of maintaining up-to-date software versions to protect against known vulnerabilities.