CVE-2017-18518 in bws-smtp Plugin
Summary
by MITRE
The bws-smtp plugin before 1.1.0 for WordPress has multiple XSS issues.
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Analysis
by VulDB Data Team • 11/27/2023
The bws-smtp plugin for WordPress prior to version 1.1.0 contained multiple cross-site scripting vulnerabilities that exposed WordPress installations to significant security risks. These vulnerabilities arose from insufficient input validation and output sanitization within the plugin's codebase, specifically affecting the plugin's handling of user-supplied data in various administrative and frontend contexts. The flaw allowed malicious actors to inject malicious scripts into WordPress admin interfaces and user-facing pages, potentially compromising the entire WordPress ecosystem. The vulnerability was particularly concerning as it affected the plugin's email configuration and management interfaces where administrators would input various parameters and settings. The XSS flaws were present in multiple locations throughout the plugin's code, including areas responsible for processing email server configurations, authentication credentials, and custom email templates. Attackers could exploit these vulnerabilities by crafting malicious input within the plugin's administrative forms, which would then be executed in the browsers of other users who viewed the affected pages. This type of vulnerability falls under CWE-79, Cross-Site Scripting, and represents a critical weakness in the plugin's data handling mechanisms. The impact extended beyond simple script execution as it could enable attackers to steal administrative credentials, modify plugin configurations, or even redirect users to malicious websites. The vulnerability was particularly dangerous in environments where multiple administrators had access to the plugin's settings, as it could allow privilege escalation or unauthorized modifications to email delivery systems. According to ATT&CK framework, this vulnerability maps to T1059.001 for command and scripting interpreter and T1566.001 for spearphishing attachment, as attackers could leverage the XSS to deliver additional payloads or manipulate email delivery processes. The plugin's failure to properly sanitize user inputs before rendering them in HTML contexts created persistent XSS opportunities that could affect any user who accessed the compromised administrative interfaces. These vulnerabilities were especially severe because they occurred within a plugin that handled sensitive email configurations, potentially allowing attackers to intercept email communications or manipulate the email delivery infrastructure. The security implications were compounded by the fact that many WordPress administrators might not have been aware of the plugin's vulnerabilities or might have lacked proper security monitoring in place to detect the exploitation attempts. Organizations using affected versions of the bws-smtp plugin faced significant risk of unauthorized access to email systems and potential data exfiltration through the manipulation of email delivery parameters. The remediation required updating to version 1.1.0 or later, which included proper input validation and output sanitization measures to prevent the execution of malicious scripts. Security professionals should have implemented immediate monitoring for exploitation attempts and ensured all WordPress installations were updated to prevent these vulnerabilities from being leveraged in broader attacks against WordPress environments. The incident highlighted the importance of thorough security testing for WordPress plugins and the necessity of maintaining up-to-date software versions to prevent exploitation of known vulnerabilities in third-party components.