CVE-2006-2491 in BoastMachine
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in (1) index.php and (2) bmc/admin.php in BoastMachine (bMachine) 3.1 and earlier allows remote attackers to inject arbitrary web script or HTML via the query string, which is not properly filtered when it is accessed using the $_SERVER["PHP_SELF"] variable.
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Analysis
by VulDB Data Team • 08/04/2025
The vulnerability identified as CVE-2006-2491 represents a critical cross-site scripting flaw within BoastMachine version 3.1 and earlier, specifically affecting two key application components including index.php and bmc/admin.php. This weakness stems from inadequate input validation and sanitization mechanisms that fail to properly filter user-supplied data before it is processed and rendered within the web application's response. The vulnerability occurs when the application utilizes the $_SERVER["PHP_SELF"] variable to capture and display query string parameters without implementing proper security measures to prevent malicious script injection.
The technical implementation of this vulnerability leverages the PHP_SELF server variable which contains the filename of the currently executing script, including any query string parameters that were part of the original request. When BoastMachine applications process these parameters through the $_SERVER["PHP_SELF"] variable without proper sanitization, they create an environment where attackers can inject malicious HTML or JavaScript code directly into the application's output. This injection occurs because the application fails to validate or escape the query string content before incorporating it into dynamic web pages, making it susceptible to exploitation by remote attackers who can craft malicious URLs containing script payloads.
The operational impact of this vulnerability extends beyond simple data theft or defacement, as it provides attackers with the capability to execute arbitrary code within the context of users' browsers. This can lead to session hijacking, credential theft, redirection to malicious sites, and potentially full compromise of user accounts. The vulnerability affects both public-facing index.php pages and administrative functions in bmc/admin.php, meaning that attackers could potentially gain access to sensitive administrative interfaces or manipulate the application's behavior for unauthorized purposes. The widespread use of BoastMachine in content management and blogging applications increases the potential attack surface significantly.
Security professionals should recognize this vulnerability as a classic example of CWE-79: Improper Neutralization of Input During Web Page Generation, which falls under the broader category of web application security weaknesses. The flaw aligns with ATT&CK technique T1059.007: Command and Scripting Interpreter: JavaScript, as it enables attackers to execute malicious JavaScript code through web-based interfaces. Organizations should implement immediate mitigations including input validation, output encoding, and proper sanitization of all user-supplied data before processing. The most effective remediation involves implementing proper HTML entity encoding for all dynamic content and employing robust input validation frameworks that filter out potentially malicious characters and script tags from query parameters. Additionally, developers should avoid using $_SERVER["PHP_SELF"] for displaying user-controllable data and instead implement proper parameter validation and sanitization at the application level to prevent such injection attacks from succeeding.