CVE-2021-38607 in JetEngine
Summary
by MITRE • 08/16/2021
Crocoblock JetEngine before 2.6.1 allows XSS by remote authenticated users via a custom form input.
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Analysis
by VulDB Data Team • 08/18/2021
The vulnerability CVE-2021-38607 affects Crocoblock JetEngine versions prior to 2.6.1 and represents a cross-site scripting flaw that can be exploited by remote authenticated users. This issue resides within the custom form input handling functionality of the plugin, which is commonly used for creating various web forms and data collection mechanisms. The vulnerability allows attackers who have already gained authentication credentials to inject malicious scripts into form fields that are then executed in the context of other users' browsers. This represents a significant security risk as it can be leveraged to escalate privileges or perform unauthorized actions on behalf of legitimate users.
The technical flaw manifests in the improper sanitization and validation of user input within custom form fields. When authenticated users submit data through custom forms created with JetEngine, the system fails to adequately filter or encode special characters that could be interpreted as HTML or JavaScript code. This lack of input validation creates an environment where malicious actors can inject script payloads that persist in the form data storage and execute whenever the form data is rendered or processed. The vulnerability specifically impacts the custom form input functionality, which is a core component of JetEngine's form-building capabilities and is widely used across WordPress installations.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable attackers to perform various malicious activities within the compromised environment. An authenticated attacker could inject scripts that steal session cookies, redirect users to malicious websites, modify form data, or even execute commands on the affected system. This vulnerability is particularly dangerous because it requires only authentication credentials rather than exploiting a separate authentication bypass, making it accessible to users who have already gained access through other means. The attack vector is facilitated through the standard form submission process, which makes detection more challenging as the malicious input appears to be legitimate user activity.
Mitigation strategies for CVE-2021-38607 should focus on immediate patching of the affected JetEngine plugin to version 2.6.1 or later, which contains the necessary fixes for the input validation issues. Organizations should also implement additional security measures such as input sanitization at multiple layers, including application-level filtering, output encoding for all form data, and regular security audits of form handling components. Network monitoring should be enhanced to detect unusual form submission patterns that might indicate exploitation attempts. The vulnerability aligns with CWE-79, which describes cross-site scripting flaws in web applications, and can be categorized under ATT&CK technique T1059.007 for scripting languages, particularly when attackers leverage the vulnerability to execute malicious scripts within user browsers. Regular security assessments and vulnerability scanning should be implemented to identify similar issues in other plugins and themes that may be susceptible to similar input validation flaws.