CVE-2023-34845 in Bludit
Summary
by MITRE • 06/16/2023
Bludit v3.14.1 was discovered to contain an arbitrary file upload vulnerability in the component /admin/new-content. This vulnerability allows attackers to execute arbitrary web scripts or HTML via uploading a crafted SVG file.
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Analysis
by VulDB Data Team • 08/02/2024
The vulnerability identified as CVE-2023-34845 represents a critical arbitrary file upload flaw in Bludit content management system version 3.14.1. This vulnerability exists within the administrative component /admin/new-content which handles content creation and media uploads. The flaw stems from insufficient input validation and sanitization mechanisms that fail to properly inspect or restrict file types during the upload process. Attackers can exploit this weakness by crafting malicious SVG files that appear legitimate but contain embedded malicious scripts or code that executes when the file is processed or displayed within the web application environment.
The technical implementation of this vulnerability aligns with CWE-434 which categorizes insecure file upload handling as a significant security risk. The flaw specifically manifests when the application accepts SVG files without proper validation of their content structure or embedded code elements. SVG files are particularly dangerous in this context because they support embedded scripting capabilities through javascript within the xml structure, making them ideal for cross-site scripting attacks. The vulnerability allows attackers to bypass typical file type restrictions and upload files that contain malicious javascript payloads, HTML content, or other harmful code elements that can execute in the context of the victim's browser session.
From an operational impact perspective, this vulnerability enables attackers to achieve arbitrary code execution on the target web server, potentially leading to complete system compromise. The attack surface is significant as it directly targets the administrative interface where privileged users manage content, making it a prime target for attackers seeking persistent access. Successful exploitation can result in data breaches, unauthorized content modification, privilege escalation, and potential lateral movement within the network. The vulnerability is particularly concerning because it allows for the execution of web scripts and HTML content, which can be leveraged to establish persistent backdoors, steal session cookies, or redirect users to malicious sites.
The security implications extend beyond simple code execution to encompass broader attack vectors including persistent XSS, session hijacking, and potential privilege escalation attacks. Attackers can leverage this vulnerability to inject malicious code that persists across server restarts, making detection and remediation more challenging. The attack chain typically involves uploading a malicious SVG file through the vulnerable upload endpoint, followed by triggering the execution of embedded code through various user interactions or automated processes within the application. This vulnerability directly maps to several ATT&CK techniques including T1505.003 for Web Shell deployment and T1203 for Exploitation for Client Execution, demonstrating the comprehensive attack surface this flaw exposes.
Mitigation strategies should focus on implementing robust input validation, content type checking, and file extension restrictions within the upload component. Organizations should immediately apply the vendor-provided patch or upgrade to a version that addresses this vulnerability. Additional protective measures include implementing strict file content validation for SVG files, removing unnecessary file upload capabilities, and employing web application firewalls to monitor and block suspicious upload patterns. The security posture should also include regular security assessments of administrative interfaces and comprehensive monitoring for unauthorized file uploads or suspicious user activities within the application's content management system.