CVE-2023-33797 in Netbox
Summary
by MITRE • 05/24/2023
A stored cross-site scripting (XSS) vulnerability in the Create Sites (/dcim/sites/) function of Netbox v3.5.1 allows attackers to execute arbitrary web scripts or HTML via a crafted payload injected into the Name field.
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Analysis
by VulDB Data Team • 06/17/2023
The vulnerability identified as CVE-2023-33797 represents a critical stored cross-site scripting flaw within the Netbox network management platform version 3.5.1. This issue specifically affects the Create Sites functionality located within the Data Center Infrastructure Management (DCIM) module, where user input is not properly sanitized before being rendered back to other users. The vulnerability exists in the Name field of the site creation form, making it a prime target for attackers seeking to persist malicious scripts within the application's database. When victims view the affected site entries, their browsers execute the injected malicious code, potentially leading to session hijacking, data exfiltration, or further exploitation of the compromised systems.
The technical implementation of this vulnerability stems from insufficient input validation and output encoding mechanisms within the Netbox application's backend processing. Attackers can craft malicious payloads containing script tags or other HTML elements that are stored in the database when the site is created. These payloads remain persistent until explicitly deleted or modified, allowing attackers to maintain long-term access to the system. The vulnerability maps directly to CWE-79, which describes Cross-Site Scripting flaws where untrusted data is improperly handled during web page generation. This particular implementation represents a stored XSS variant where the malicious input is saved to the server and executed against other users who view the affected content, rather than requiring immediate interaction with a malicious link.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable attackers to escalate privileges within the Netbox environment and potentially access sensitive network infrastructure data. Since Netbox serves as a critical component for network infrastructure management, attackers who successfully exploit this vulnerability could gain visibility into network topology, device configurations, and other sensitive information. The attack surface is particularly concerning given that the vulnerability affects a core administrative function, allowing unauthorized users to inject malicious code that executes in the context of other authenticated users. This scenario aligns with ATT&CK technique T1531, which involves using malicious code to gain access to network resources, and T1071.004, which covers application layer protocol usage for command and control communications.
Mitigation strategies for CVE-2023-33797 should prioritize immediate patching of the Netbox application to version 3.5.2 or later, which contains the necessary fixes for the XSS vulnerability. Organizations should also implement additional defensive measures including input sanitization at multiple layers, output encoding for all user-provided content, and regular security scanning of the application environment. Network segmentation and access controls should be enforced to limit the potential impact of successful exploitation, while monitoring systems should be configured to detect anomalous user behavior patterns that might indicate compromise. Security teams should conduct thorough code reviews focusing on input validation mechanisms and ensure that all user-supplied data is properly escaped before being rendered in web contexts. The vulnerability demonstrates the importance of implementing defense-in-depth strategies, as proper input validation and output encoding could have prevented the exploitation regardless of other security controls.