CVE-2002-0681 in Webserver
Summary
by MITRE
Cross-site scripting vulnerability in GoAhead Web Server 2.1 allows remote attackers to execute script as other web users via script in a URL that generates a "404 not found" message, which does not quote the script.
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Analysis
by VulDB Data Team • 05/31/2025
The CVE-2002-0681 vulnerability represents a classic cross-site scripting flaw in the GoAhead Web Server version 2.1 that demonstrates how improper input sanitization can lead to severe security implications. This vulnerability specifically targets the server's handling of malformed URLs that trigger 404 error responses, creating an environment where malicious scripts can be injected and executed within the context of other users' browsers.
The technical exploitation of this vulnerability occurs when a remote attacker crafts a malicious URL that, when processed by the vulnerable GoAhead server, generates a 404 not found error message. The flaw lies in the server's failure to properly quote or escape the script content within the error response, allowing the injected JavaScript code to be rendered directly in the browser. This unescaped output creates a persistent XSS vector that can be leveraged by attackers to execute arbitrary scripts in the victim's browser context.
This vulnerability operates under the CWE-79 category of Cross-Site Scripting, specifically demonstrating how improper output escaping in error handling routines can create attack surfaces. The operational impact extends beyond simple script execution as it allows attackers to potentially steal session cookies, redirect users to malicious sites, or perform actions on behalf of authenticated users. The vulnerability is particularly dangerous because it exploits the server's standard error handling mechanism rather than requiring specific user interaction or privileged access.
The attack vector in this case is relatively straightforward yet effective, as it requires only that a victim visit a maliciously crafted URL that triggers the vulnerable 404 response generation. This makes the vulnerability particularly dangerous in environments where users might encounter malformed links or where web crawlers might inadvertently trigger the vulnerable code path. The lack of proper output sanitization in the error response means that any script content included in the URL gets directly embedded into the HTML response without proper escaping.
Security professionals should note that this vulnerability highlights the importance of consistent input validation and output escaping across all server responses, including error messages. The flaw demonstrates how even standard server functionality can become a security risk when proper sanitization practices are not implemented. Organizations using GoAhead Web Server 2.1 should prioritize immediate patching or mitigation strategies, as the vulnerability provides attackers with a reliable method to execute arbitrary code in user browsers without requiring authentication or complex attack chains. The ATT&CK framework would categorize this under T1566.001 - Phishing via Service and T1059.007 - Command and Scripting Interpreter, as it enables the execution of malicious scripts through web-based attack vectors.