CVE-2005-1116

Vulnerability

A cross-site scripting (XSS) vulnerability exists in the Calendar module of phpBB (specifically phpBB Plus v.1.52 and below) [1]. The flaw resides in calendar_scheduler.php where the start parameter is not properly sanitized before being reflected in the page output. An attacker can inject arbitrary HTML or JavaScript code through this parameter, which will be executed in the context of the victim's browser when the crafted URL is visited.

Exploitation

An attacker can exploit this vulnerability by crafting a malicious URL containing a start parameter with embedded script code, such as ``. No authentication or special privileges are required; the victim simply needs to click the link or be redirected to the crafted URL. The injected script executes in the security context of the vulnerable phpBB site.

Impact

Successful exploitation allows the attacker to execute arbitrary web script or HTML in the victim's browser. This can lead to session hijacking (cookie theft), defacement of the page, or redirection to malicious sites. The attacker gains the ability to perform actions on behalf of the victim within the phpBB application, potentially compromising user accounts and sensitive data.

Mitigation

As of the publication date (2005-05-02), no official patch or fixed version has been identified in the available references [1]. Users are advised to upgrade to a later version of phpBB or phpBB Plus if a security update becomes available. Alternatively, input validation and output encoding for the start parameter should be implemented as a workaround. This vulnerability is not listed in CISA's Known Exploited Vulnerabilities (KEV) catalog.