CVE-2024-44049 in Gutenberg Blocks Plugin
Summary
by MITRE • 09/18/2024
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in ThemeHunk Gutenberg Blocks unlimited-blocks.This issue affects Gutenberg Blocks: from n/a through <= 1.2.8.
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Analysis
by VulDB Data Team • 04/02/2026
This cross-site scripting vulnerability resides within the ThemeHunk Gutenberg Blocks plugin, specifically in the unlimited-blocks component where user input fails to be properly sanitized during web page generation processes. The flaw represents a classic XSS vulnerability that allows malicious actors to inject malicious scripts into web pages viewed by other users. The vulnerability impacts versions of the plugin from the initial release through version 1.2.8, indicating a prolonged period where the sanitization mechanisms were inadequate to prevent script injection attacks. The improper neutralization occurs during the rendering of content blocks where user-provided data enters the web page generation cycle without appropriate validation or encoding measures. This vulnerability falls under CWE-79 which specifically addresses cross-site scripting flaws in web applications and aligns with ATT&CK technique T1203 which involves exploiting web application vulnerabilities to execute malicious code.
The technical implementation of this vulnerability stems from insufficient input validation within the Gutenberg blocks rendering engine where user content is directly incorporated into HTML output without proper HTML escaping or sanitization. When users create or edit content using the affected blocks, any malicious script tags or JavaScript code entered in text fields or content areas can be executed in the browsers of other users who view the generated pages. The attack vector typically involves an attacker crafting malicious input that gets stored in the WordPress database and subsequently rendered on web pages without proper sanitization. This creates a persistent threat where the malicious code executes whenever any user accesses the affected content, potentially leading to session hijacking, credential theft, or redirection to malicious sites. The vulnerability is particularly dangerous in environments where multiple users have access to content creation features, as it can be exploited to compromise user sessions and persistently deliver malicious payloads.
The operational impact of this vulnerability extends beyond simple script execution to encompass potential data breaches, session manipulation, and broader system compromise. Attackers can leverage this vulnerability to steal user cookies, execute unauthorized actions on behalf of users, or redirect victims to phishing sites that mimic legitimate services. The persistent nature of stored XSS attacks means that once the malicious payload is injected, it continues to affect all users who access the compromised content until the vulnerability is patched or the malicious content is removed. Organizations using this plugin may experience unauthorized access to sensitive data, compromised user accounts, and potential regulatory violations if user data is accessed without proper authorization. The vulnerability also affects the integrity of the website content, as attackers can modify the appearance or functionality of web pages to mislead users or disrupt normal operations.
Mitigation strategies for this vulnerability should include immediate patching of the affected plugin to version 1.2.9 or later where the sanitization issues have been addressed. Administrators should implement comprehensive input validation and output encoding mechanisms that ensure all user-provided content is properly escaped before being rendered in web pages. Regular security audits should be conducted to identify similar vulnerabilities in other plugins or themes that may not have been properly sanitized. Network monitoring solutions should be deployed to detect suspicious script execution patterns or unusual traffic patterns that might indicate exploitation attempts. Additionally, implementing content security policies and restricting user permissions for content creation can reduce the attack surface. Organizations should also maintain regular security updates and consider using web application firewalls to detect and block malicious input attempts. The remediation process should include thorough testing of the patched version to ensure that legitimate functionality remains intact while the XSS vulnerability is properly addressed, following security best practices outlined in the OWASP Top Ten and NIST cybersecurity guidelines.