CVE-2017-18559 in cforms2 Plugin
Summary
by MITRE
The cforms2 plugin before 14.13.3 for WordPress has multiple XSS issues.
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Analysis
by VulDB Data Team • 11/28/2023
The cforms2 plugin for WordPress prior to version 14.13.3 contains multiple cross-site scripting vulnerabilities that pose significant security risks to affected websites. These vulnerabilities arise from insufficient input validation and output sanitization within the plugin's form handling mechanisms, allowing malicious actors to inject malicious scripts into web pages viewed by other users. The flaw affects the plugin's ability to properly escape and validate user-supplied data before rendering it in web responses, creating persistent opportunities for attackers to execute arbitrary JavaScript code within the context of victims' browsers.
The technical implementation of these XSS vulnerabilities stems from the plugin's failure to adequately sanitize form field inputs and dynamic content generation. Attackers can exploit these weaknesses by crafting malicious payloads in form fields or parameters that are then processed and displayed without proper escaping mechanisms. This allows for the execution of malicious scripts that can steal session cookies, perform unauthorized actions on behalf of users, or redirect them to malicious sites. The vulnerability is particularly concerning because it affects the core form processing functionality of the plugin, which is typically used for collecting user data through contact forms, surveys, and other interactive web elements.
The operational impact of CVE-2017-18559 extends beyond simple script execution, as it can enable attackers to perform a wide range of malicious activities including credential theft, session hijacking, and data exfiltration. When exploited, these vulnerabilities can compromise the integrity of user interactions with WordPress sites, potentially leading to complete account takeovers, unauthorized access to sensitive data, and damage to the reputation of affected organizations. The persistent nature of these XSS flaws means that once an attacker successfully injects malicious code, it can affect all users who view the compromised pages until the vulnerability is patched and the malicious content is removed from the database.
Security practitioners should prioritize immediate remediation of this vulnerability through updating the cforms2 plugin to version 14.13.3 or later, which includes proper input validation and output sanitization measures. Additional defensive measures include implementing content security policies, monitoring for suspicious form submissions, and conducting regular security audits of WordPress plugins. Organizations should also consider implementing web application firewalls to detect and block known XSS attack patterns, while ensuring that all user inputs are properly escaped before being rendered in web pages. The vulnerability aligns with CWE-79, which specifically addresses cross-site scripting flaws in web applications, and represents a common attack vector categorized under ATT&CK technique T1566.001 for initial access through malicious web content, highlighting the critical importance of maintaining up-to-date security controls in content management systems.
The exploitation of this vulnerability demonstrates the ongoing challenges in WordPress plugin security where third-party components can introduce significant risks to entire web platforms. Regular security assessments and patch management procedures become essential defensive measures, as the timeframe between vulnerability disclosure and exploitation often allows attackers to compromise numerous systems. Organizations should maintain comprehensive inventory of all installed plugins and their versions, enabling rapid identification and remediation of similar vulnerabilities across their digital infrastructure.