CVE-2026-9677 in Shariff for WordPress Plugin
Summary
by MITRE • 06/27/2026
The Shariff for WordPress Shariff for WordPress plugin through 1.0.11 does not sanitize or escape the shariff_infourl setting before outputting it in the frontend HTML via the generateshariff() function, which could allow high privilege users such as admin to perform Stored Cross-Site Scripting attacks even when the unfiltered_html capability is disallowed (for example in multisite setup).
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Analysis
by VulDB Data Team • 06/27/2026
The Shariff for WordPress plugin vulnerability represents a critical stored cross-site scripting flaw that affects versions through 1.0.11, exposing websites to persistent malicious code execution. This vulnerability specifically resides in the plugin's handling of the shariff_infourl setting parameter within the generateshariff() function, where user-supplied input fails to undergo proper sanitization or escaping before being rendered in frontend HTML output. The flaw is particularly concerning because it targets high-privilege users including administrators who possess the capability to manipulate plugin settings, creating a vector for persistent XSS attacks that can evade standard WordPress security measures.
The technical implementation of this vulnerability stems from inadequate input validation and output escaping mechanisms within the plugin's core functionality. When administrators configure the shariff_infourl setting through the WordPress admin interface, the plugin stores this value without proper sanitization processes that would normally occur in WordPress's esc_attr() or similar escaping functions. The generateshariff() function then directly incorporates this unsanitized data into HTML markup, creating an environment where malicious scripts can be executed whenever the frontend page containing the Shariff widget is rendered. This stored nature of the vulnerability means that once exploited, the malicious payload persists until manually removed from the plugin settings, making it particularly dangerous in multi-user environments.
The operational impact of this vulnerability extends beyond simple script execution, as it provides attackers with elevated privileges within the WordPress environment. Even when WordPress multisite installations restrict the unfiltered_html capability for regular users, administrators can still leverage this flaw to execute malicious code on behalf of other users, potentially leading to complete site compromise. The vulnerability's exploitation requires minimal prerequisites beyond administrative access to the plugin settings, making it accessible to attackers who have gained administrative privileges through other means such as credential theft or privilege escalation attacks. This scenario aligns with ATT&CK technique T1059.001 for command and scripting interpreter execution and T1546.001 for system binary proxy execution.
Security implications of this vulnerability encompass potential data exfiltration, session hijacking, and complete administrative control over affected websites. Attackers can inject malicious JavaScript that monitors user interactions, steals cookies, or redirects users to phishing sites, while the stored nature of the vulnerability ensures these attacks persist across multiple page views and user sessions. The CWE classification for this vulnerability falls under CWE-79: Improper Neutralization of Input During Web Page Generation, specifically addressing cross-site scripting scenarios where output escaping fails to properly sanitize user-controllable data.
Mitigation strategies should prioritize immediate plugin updates to versions that address the sanitization flaw, while administrators should implement additional security measures including restricting administrative access to only trusted users, monitoring plugin configuration changes, and implementing content security policies. Regular security audits of WordPress plugins should include verification of input sanitization practices and output escaping mechanisms, with particular attention to settings that are directly rendered in HTML contexts. The vulnerability also highlights the importance of proper capability checks within WordPress plugins, ensuring that even privileged users cannot bypass standard security restrictions through plugin-specific flaws. Organizations should consider implementing automated monitoring solutions that can detect unusual changes to plugin configurations and alert administrators to potential exploitation attempts.