CVE-2018-16206 in spam-byebye Plugin
Summary
by MITRE
Cross-site scripting vulnerability in WordPress plugin spam-byebye 2.2.1 and earlier allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.
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Analysis
by VulDB Data Team • 04/29/2020
The CVE-2018-16206 vulnerability represents a critical cross-site scripting flaw within the WordPress plugin spam-byebye version 2.2.1 and earlier. This vulnerability exposes WordPress installations to potential exploitation by malicious actors who can inject arbitrary web scripts or HTML content through unspecified attack vectors. The flaw exists within the plugin's handling of user input or data processing mechanisms, creating an opportunity for attackers to execute malicious code within the context of a victim's browser session. The vulnerability's impact extends beyond simple data theft as it can enable more sophisticated attacks including session hijacking, credential theft, and the delivery of additional malware payloads to unsuspecting users.
The technical nature of this XSS vulnerability aligns with CWE-79, which specifically addresses cross-site scripting flaws in web applications. This classification indicates that the plugin fails to properly sanitize or validate user-supplied input before rendering it within web pages. The unspecified vectors suggest that the vulnerability could be triggered through multiple entry points within the plugin's functionality, potentially including administrative interfaces, user-facing forms, or data processing endpoints. Attackers could leverage this weakness to inject malicious scripts that would execute whenever other users view affected pages or interact with the compromised plugin functionality. The vulnerability's presence in the spam-byebye plugin specifically indicates that it may be exploited through spam-related data handling or reporting mechanisms.
The operational impact of this vulnerability creates significant risks for WordPress site administrators and their visitors. When exploited, the XSS flaw allows attackers to perform actions such as stealing user cookies, modifying website content, redirecting users to malicious sites, or executing arbitrary commands within the victim's browser context. The vulnerability's persistence in versions up to 2.2.1 means that numerous WordPress installations remained exposed for an extended period, potentially allowing attackers to harvest credentials, conduct phishing attacks, or establish persistent access to compromised sites. The attack surface is particularly concerning given that spam-byebye plugins are commonly used for email spam protection, making them attractive targets for adversaries seeking to compromise email security systems.
Mitigation strategies for CVE-2018-16206 should prioritize immediate plugin updates to versions that address the XSS vulnerability. System administrators must ensure that all instances of the spam-byebye plugin are upgraded to versions 2.2.2 or later where the vulnerability has been patched. Additionally, implementing proper input validation and output encoding mechanisms within the plugin's codebase would prevent similar issues from occurring in the future. Security monitoring should include regular scanning for outdated plugins and vulnerable components within WordPress installations. The remediation process should also involve reviewing and testing updated plugin functionality to ensure that security patches do not introduce compatibility issues or break existing features. Organizations should consider implementing web application firewalls and content security policies as additional protective measures against similar XSS vulnerabilities. The ATT&CK framework categorizes such vulnerabilities under the 'Command and Control' and 'Credential Access' tactics, highlighting the potential for attackers to establish persistent access and exfiltrate sensitive information through these XSS exploits.