CVE-2018-16204 in XML Sitemaps
Summary
by MITRE
Cross-site scripting vulnerability in Google XML Sitemaps Version 4.0.9 and earlier allows remote authenticated attackers to inject arbitrary web script or HTML via unspecified vectors.
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Analysis
by VulDB Data Team • 04/27/2020
This cross-site scripting vulnerability exists in Google XML Sitemaps plugin version 4.0.9 and earlier, representing a critical security flaw that enables authenticated attackers to execute malicious scripts within the context of affected websites. The vulnerability stems from inadequate input validation and output sanitization mechanisms within the plugin's codebase, allowing attackers with valid credentials to inject arbitrary web scripts or HTML content into the application's response. The unspecified vectors suggest that the flaw could manifest through multiple attack surfaces within the plugin's functionality, potentially affecting various user-facing interfaces or administrative panels where user input is processed.
The technical implementation of this vulnerability aligns with CWE-79, which specifically addresses cross-site scripting flaws in web applications. This classification indicates that the plugin fails to properly escape or filter user-supplied data before rendering it in web pages, creating opportunities for attackers to inject malicious payloads that execute in the browsers of other users. The authenticated nature of the attack means that adversaries must first obtain valid user credentials, but once compromised, they can leverage this vulnerability to perform actions such as stealing session cookies, redirecting users to malicious sites, or defacing website content. This weakness directly violates the principle of least privilege and demonstrates inadequate security controls in the plugin's data handling processes.
The operational impact of this vulnerability extends beyond simple script injection, as it provides attackers with a potential foothold for more sophisticated attacks within the compromised WordPress environment. Successful exploitation could enable attackers to escalate privileges, modify website content, steal sensitive user data, or establish persistent backdoors through the injected scripts. The vulnerability affects not only individual website owners but also creates risks for entire WordPress installations that rely on the plugin for sitemap generation and SEO optimization. From an attacker's perspective, this vulnerability represents a valuable tool for conducting targeted attacks against WordPress sites, particularly those with less security-conscious administrators who may not regularly update their plugins.
Mitigation strategies should prioritize immediate plugin updates to versions that address the XSS vulnerability, as Google has likely released patches to resolve the issue. System administrators must implement comprehensive security monitoring to detect any suspicious activities or unauthorized modifications to sitemap files or plugin configurations. Additional protective measures include implementing web application firewalls that can detect and block malicious script injection attempts, enforcing strict input validation rules for all user-supplied data, and conducting regular security audits of installed plugins. Organizations should also consider implementing content security policies that limit script execution permissions and regularly review user access controls to minimize the risk of privilege escalation through this vulnerability. The ATT&CK framework categorizes this type of vulnerability under the T1059.007 technique for scripting languages, highlighting the importance of validating all script execution contexts and implementing proper input sanitization measures.