CVE-2020-13643 in SiteOrigin Page Builder Plugin
Summary
by MITRE
An issue was discovered in the SiteOrigin Page Builder plugin before 2.10.16 for WordPress. The live editor feature did not do any nonce verification, allowing for requests to be forged on behalf of an administrator. The live_editor_panels_data $_POST variable allows for malicious JavaScript to be executed in the victim's browser.
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Analysis
by VulDB Data Team • 10/19/2020
The vulnerability identified as CVE-2020-13643 resides within the SiteOrigin Page Builder plugin for WordPress, specifically affecting versions prior to 2.10.16. This represents a critical security flaw that undermines the integrity of the plugin's live editor functionality and exposes WordPress sites to significant exploitation risks. The issue stems from the absence of proper nonce verification mechanisms within the live editor component, creating a pathway for authenticated attackers to manipulate administrative sessions and execute malicious code within victim browsers.
The technical flaw manifests through the live_editor_panels_data $_POST variable which is utilized by the plugin's live editing interface. This variable lacks proper validation and authentication checks, allowing attackers to forge requests that appear to originate from legitimate administrators. The absence of nonce verification means that any user with access to the live editor interface can potentially impersonate administrators and perform privileged actions. This vulnerability directly maps to CWE-346, which addresses "Improper Verification of Cryptographic Signature", as the missing nonce validation creates a scenario where requests cannot be properly authenticated. The vulnerability also aligns with CWE-862, "Missing Authorization", since the system fails to verify that requests are properly authorized before processing them.
The operational impact of this vulnerability extends beyond simple privilege escalation, as it enables arbitrary code execution within administrator browsers. When malicious JavaScript is injected through the live editor, it can execute with the full privileges of the administrator account, potentially leading to complete compromise of the WordPress installation. Attackers can leverage this vulnerability to install malware, steal administrative credentials, modify content, or establish persistent backdoors. The attack surface is particularly concerning because the live editor is typically accessible to users with administrator privileges, making it a prime target for exploitation. This vulnerability can be exploited through various attack vectors including social engineering campaigns that trick administrators into executing malicious code within the editor interface, or through automated exploitation if the vulnerability exists in a publicly accessible context.
The exploitation of CVE-2020-13643 follows patterns consistent with the ATT&CK framework's privilege escalation and execution tactics. Specifically, this vulnerability aligns with T1059.007 "Command and Scripting Interpreter: JavaScript' and T1548.002 'Abuse Elevation Control Mechanism: Bypass User Account Control', as it allows for JavaScript execution with elevated privileges. The vulnerability also maps to T1484.001 'Domain Policy Modification: Group Policy Modification' when considering the potential for administrators to be compromised and used to modify domain policies or configurations. Organizations affected by this vulnerability should immediately implement mitigations including updating to SiteOrigin Page Builder version 2.10.16 or later, implementing additional access controls for the live editor functionality, and monitoring for suspicious administrative activities. Network segmentation and monitoring of POST requests to the live editor endpoints should be implemented to detect potential exploitation attempts. The vulnerability also highlights the importance of proper input validation and authentication mechanisms in web applications, as the absence of nonce verification creates a fundamental security flaw that can be exploited to bypass authentication and authorization controls.