CVE-2005-4162 in PerlCal
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in cal_make.pl in ACME PerlCal 2.99.20 allows remote attackers to inject arbitrary web script or HTML via the p0 parameter.
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Analysis
by VulDB Data Team • 07/14/2018
The vulnerability identified as CVE-2005-4162 represents a classic cross-site scripting flaw within the ACME PerlCal 2.99.20 web application. This issue resides in the cal_make.pl script which processes user input through the p0 parameter, creating an avenue for malicious actors to execute arbitrary web scripts or HTML code within the context of other users' browsers. The vulnerability stems from inadequate input validation and output sanitization mechanisms that fail to properly escape or filter user-supplied data before incorporating it into dynamic web content.
This cross-site scripting vulnerability operates under the Common Weakness Enumeration classification of CWE-79, which specifically addresses improper neutralization of input during web page generation. The flaw allows remote attackers to inject malicious payloads through the p0 parameter, which is typically used for calendar-related data processing within the PerlCal application. When a victim accesses a page containing the maliciously crafted input, the injected script executes in their browser session, potentially leading to session hijacking, credential theft, or redirection to malicious websites.
The operational impact of this vulnerability extends beyond simple script injection, as it can be leveraged for more sophisticated attacks within the context of web application security. Attackers can exploit this weakness to manipulate calendar displays, inject malicious advertisements, or even create persistent XSS payloads that remain active until the application is updated or the affected parameter is cleared. The vulnerability affects users who interact with the PerlCal application, particularly those who may be logged into administrative or user accounts, as the malicious script executes with the privileges of the victim's session.
Mitigation strategies for this vulnerability should encompass multiple layers of defense including immediate input validation and output encoding of all user-supplied parameters, particularly those used in dynamic content generation. Organizations should implement proper HTML escaping routines that convert special characters such as angle brackets, quotes, and script tags into their encoded equivalents before rendering user input. The recommended approach aligns with ATT&CK technique T1203, which focuses on input validation and sanitization to prevent malicious code execution. Additionally, regular security updates and patches to the PerlCal application should be prioritized, as this vulnerability has been addressed in subsequent releases through improved parameter handling and sanitization mechanisms.
The broader implications of this vulnerability highlight the critical importance of secure coding practices in web applications, particularly in legacy systems that may not have undergone modern security reviews. This flaw demonstrates how simple input parameter handling can create significant security risks when proper sanitization techniques are not implemented. Organizations should conduct comprehensive security assessments of their web applications to identify similar vulnerabilities, as the absence of proper input validation represents one of the most prevalent attack vectors in web application security. The vulnerability also underscores the necessity of implementing Content Security Policy headers and other browser-based protections that can help mitigate the impact of XSS attacks even when server-side protections fail.