CVE-2002-1009 in Lil HTTP Server
Summary
by MITRE
Cross-site scripting vulnerability in PowerBASIC pbcgi.cgi, as included in Lil HTTP web server, allows remote attackers to execute arbitrary web script in other web browsers via the (1) "Name" or (2) "E-mail" parameters.
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Analysis
by VulDB Data Team • 07/07/2025
This cross-site scripting vulnerability exists within the PowerBASIC pbcgi.cgi component that is bundled with the Lil HTTP web server software. The flaw manifests when user input data is not properly sanitized before being rendered in web page responses, creating an avenue for malicious script injection. Attackers can exploit this weakness by submitting crafted payloads through the Name or E-mail parameters of the CGI script, which then get reflected back to other users browsing the affected web pages. The vulnerability represents a classic reflected XSS flaw where malicious code executes in the context of the victim's browser session, potentially enabling session hijacking or data theft.
The technical implementation of this vulnerability stems from the absence of proper input validation and output encoding mechanisms within the pbcgi.cgi script. When users enter data into the Name or E-mail fields, the application processes this information without adequate sanitization measures, allowing special characters that could be interpreted as HTML or JavaScript code. This failure to properly escape or encode user-supplied data creates an environment where attackers can inject malicious scripts that execute in the browsers of other users who view the affected content. The vulnerability affects web browsers that support JavaScript execution, making it particularly dangerous in environments where users interact with web applications regularly.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable sophisticated attacks such as credential theft, session manipulation, and redirection to malicious sites. An attacker could craft a payload that steals cookies or session tokens from unsuspecting users, effectively allowing them to impersonate legitimate users within the web application. Additionally, the reflected nature of the attack means that the malicious code must be delivered through a link or other means that triggers the vulnerable parameter, making it potentially exploitable through phishing campaigns or social engineering. The vulnerability affects any user who views pages containing the reflected malicious input, creating a wide attack surface.
Security mitigations for this vulnerability should focus on implementing comprehensive input validation and output encoding mechanisms. The most effective approach involves sanitizing all user-supplied input data by removing or escaping potentially dangerous characters such as angle brackets, quotes, and script tags before processing or displaying the information. Organizations should implement proper HTML encoding for all dynamic content rendered in web pages, ensuring that any user-provided data is treated as text rather than executable code. Additionally, deploying web application firewalls and implementing content security policies can provide additional layers of protection. This vulnerability aligns with CWE-79, which describes Cross-site Scripting flaws, and maps to ATT&CK technique T1059.007 for Scripting, specifically targeting the execution of malicious scripts in user browsers. Regular security assessments and code reviews should be conducted to identify similar vulnerabilities in other web applications and CGI scripts within the organization's infrastructure.