CVE-2026-66602 in HashBar Plugin
Summary
by MITRE • 08/19/2026
Cross-Site Request Forgery (CSRF) vulnerability in DevItems HashBar – WordPress Notification Bar allows Cross Site Request Forgery.
This issue affects HashBar – WordPress Notification Bar: from n/a through 2.0.0.
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Analysis
by VulDB Data Team • 08/19/2026
The identified security flaw represents a classic Cross-Site Request Forgery (CSRF) vulnerability within the DevItems HashBar plugin for WordPress, specifically affecting versions ranging from initial releases up to version 2.0.0. This type of attack exploits the trust that a web application has in the user's browser by tricking the user into performing unintended actions on behalf of an authenticated session. In this specific context, the vulnerability arises because the notification bar functionality fails to implement adequate anti-CSRF protections, such as unique per-session tokens or strict validation of the Origin and Referer headers during state-changing requests. Consequently, an attacker can craft a malicious webpage containing hidden forms or automated script calls that target the plugin's administrative endpoints. When a victim with active administrator privileges visits this malicious site while logged into their WordPress dashboard, the browser automatically includes valid authentication cookies in the request to the vulnerable endpoint, allowing the attacker to execute actions without the user's knowledge or consent.
From a technical perspective, the absence of synchronization tokens means that the server cannot distinguish between legitimate requests initiated by the user and forged requests generated by an external entity. This lack of verification allows for unauthorized modifications to site settings, such as altering notification bar configurations, changing theme options, or potentially modifying other plugin-specific data if those endpoints are similarly unprotected. The operational impact is significant because it enables privilege escalation attacks where a low-privilege attacker can leverage the elevated privileges of an administrator user. This could lead to defacement of the website, insertion of malicious code into notification bars that affects all visitors, or further exploitation through stored cross-site scripting if the plugin allows content injection without proper sanitization in subsequent requests.
This vulnerability aligns with CWE-352, which defines Cross-Site Request Forgery as a weakness where an application uses user-supplied input for state-changing operations without verifying intent. Furthermore, it maps to MITRE ATT&CK technique T1089, Disabling or Modifying Security Software, and potentially T1078, Valid Accounts, if the attacker leverages stolen credentials combined with CSRF to maintain persistence. The exploitation chain typically involves social engineering tactics where the victim is lured to a malicious site via phishing emails or compromised websites that host the exploit payload.
To mitigate this vulnerability, immediate action should be taken by updating the HashBar plugin to version 2.0.1 or later, which includes patches for these CSRF weaknesses. If an update is not immediately available, administrators can implement temporary mitigations such as disabling the affected functionality until a patch is released. Additionally, enforcing strict Content Security Policy headers and ensuring that all state-changing requests require unique anti-CSRF tokens are critical defensive measures. Regular security audits of WordPress plugins and adherence to secure coding standards that mandate CSRF protection for any action modifying server-side data will prevent similar issues in future deployments.