CVE-2002-1458 in L-Forum
Summary
by MITRE
Cross-site scripting vulnerability in L-Forum 2.40 and earlier, when the "Enable HTML in messages" option is on, allows remote attackers to insert arbitrary script or HTML via message fields including (1) From, (2) E-Mail, (3) Subject and (4) Body.
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Analysis
by VulDB Data Team • 09/05/2025
The vulnerability described in CVE-2002-1458 represents a classic cross-site scripting flaw that emerged in the L-Forum 2.40 software and earlier versions. This security weakness specifically manifests when the forum administrator enables the "Enable HTML in messages" feature, creating a dangerous condition where user input is not properly sanitized before being rendered in web pages. The vulnerability affects multiple message fields including the From field, Email field, Subject field, and Body field, making it particularly insidious as it can be exploited across various points of user interaction within the forum interface.
This vulnerability directly maps to CWE-79 which defines Cross-Site Scripting as a condition where untrusted data is sent to a web browser without proper validation or encoding, allowing malicious scripts to execute in the context of other users' sessions. The flaw operates by allowing attackers to inject malicious HTML or JavaScript code into the forum's message fields, which are then displayed to other users who visit those pages. When the "Enable HTML in messages" option is active, the forum application processes and renders the user-supplied content without adequate filtering mechanisms, creating a pathway for persistent script injection attacks.
The operational impact of this vulnerability extends beyond simple script execution, as it enables attackers to perform various malicious activities including session hijacking, credential theft, and data exfiltration. An attacker could craft messages containing malicious scripts that would execute whenever other users view the affected posts, potentially stealing cookies, redirecting users to malicious sites, or even modifying the forum's interface to display fraudulent content. The broad scope of affected fields means that attackers can exploit this vulnerability through multiple vectors, increasing the likelihood of successful exploitation and making defensive measures more complex to implement.
Mitigation strategies for this vulnerability should focus on implementing comprehensive input validation and output encoding mechanisms. The most effective approach involves sanitizing all user input before rendering it in web pages, particularly when HTML rendering is enabled. Organizations should disable the "Enable HTML in messages" option if it is not strictly required for forum functionality, as this eliminates the attack surface entirely. Additionally, implementing Content Security Policy headers and using proper HTML escaping techniques can provide additional layers of protection. From an ATT&CK perspective, this vulnerability aligns with techniques such as T1059.007 (Command and Scripting Interpreter: JavaScript) and T1566 (Phishing) as it enables attackers to deliver malicious scripts to victims through forum communications. The vulnerability also relates to T1213.002 (Data from Information Repositories: Forum) as it allows unauthorized access to forum content through script injection attacks, potentially compromising the integrity and confidentiality of user communications within the vulnerable system.