CVE-2023-43876 in October
Summary
by MITRE • 10/25/2023
A Cross-Site Scripting (XSS) vulnerability in installation of October v.3.4.16 allows an attacker to execute arbitrary web scripts via a crafted payload injected into the dbhost field.
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Analysis
by VulDB Data Team • 08/12/2025
The vulnerability identified as CVE-2023-43876 represents a critical cross-site scripting flaw within the October CMS installation process specifically affecting version 3.4.16. This weakness exists in the database host field validation mechanism during the initial setup phase of the content management system. The flaw stems from insufficient input sanitization and output encoding practices that fail to properly neutralize malicious script content submitted by unauthorized users. Attackers can exploit this vulnerability by crafting a malicious payload containing javascript code or other malicious scripts that gets injected into the dbhost field during installation. The vulnerability directly maps to CWE-79 which defines cross-site scripting as a weakness where untrusted data is sent to a web browser without proper validation or encoding, allowing attackers to execute arbitrary scripts in the context of the victim's browser.
During the exploitation process, the attacker submits a specially crafted dbhost value containing malicious javascript code that gets processed and rendered in the installation interface. When the vulnerable system displays this value in the user interface, the embedded script executes within the browser context of authenticated users or administrators who view the installation page. This creates a persistent XSS vector that can be leveraged for session hijacking, credential theft, or redirection to malicious sites. The attack requires minimal privileges and can be executed by any user with access to the installation interface, making it particularly dangerous for systems where installation processes are accessible to untrusted parties. The vulnerability operates at the application layer and can be classified under ATT&CK technique T1203 which describes exploitation of web applications through cross-site scripting attacks.
The operational impact of this vulnerability extends beyond simple script execution as it can enable attackers to establish persistent access to the target system through session manipulation and credential harvesting. An attacker could potentially use this vulnerability to inject malicious code that would redirect users to phishing sites or steal session cookies, effectively compromising user accounts and potentially gaining administrative access to the entire CMS installation. The vulnerability affects the integrity of the installation process and can lead to complete system compromise if attackers can manipulate the database connection parameters to point to malicious servers. Organizations using October CMS version 3.4.16 should immediately implement mitigations including input validation, output encoding, and access controls to prevent unauthorized users from accessing the installation interface. The recommended approach includes upgrading to the latest stable version of October CMS where this vulnerability has been patched, implementing proper input sanitization for all user-supplied data, and configuring web application firewalls to detect and block suspicious payloads targeting known XSS attack patterns. Additionally, organizations should conduct security assessments to ensure no malicious scripts have been injected into existing installations and review access controls to limit who can initiate or modify the installation process.