CVE-2023-33787 in Netbox
Summary
by MITRE • 05/24/2023
A stored cross-site scripting (XSS) vulnerability in the Create Tenant Groups (/tenancy/tenant-groups/) 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 stored cross-site scripting vulnerability identified as CVE-2023-33787 resides within the Netbox network management platform version 3.5.1, specifically affecting the Create Tenant Groups functionality. This vulnerability exists in the /tenancy/tenant-groups/ endpoint where user input is not properly sanitized or validated before being rendered back to users. The flaw manifests when an attacker crafts a malicious payload and injects it into the Name field during tenant group creation, which then gets stored in the application's database. When other users view the tenant group listing or details page, the malicious script executes in their browser context, potentially leading to unauthorized actions or data exfiltration.
This vulnerability falls under the CWE-79 category of Cross-Site Scripting, representing a critical security weakness in web application input validation and output encoding practices. The stored nature of this XSS flaw means that the malicious payload persists in the application's backend storage and executes whenever affected pages are accessed, making it particularly dangerous for environments where multiple users interact with shared tenant group data. The vulnerability specifically targets the input sanitization process in the tenant group creation workflow, where the application fails to properly escape or validate user-supplied data before persisting it to the database.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable attackers to escalate privileges, steal session cookies, perform unauthorized actions within the Netbox interface, or redirect users to malicious domains. In a network management environment like Netbox, where administrators and users frequently access tenant group information, this vulnerability could allow attackers to gain unauthorized access to sensitive network infrastructure data, potentially compromising the entire network management system. The attack surface is particularly concerning given that tenant groups often contain critical information about network segments, customer relationships, and infrastructure allocations that could be exploited for lateral movement within the network.
Organizations utilizing Netbox v3.5.1 should immediately implement mitigations including input validation and output encoding for all user-supplied data, particularly in fields that are rendered back to users. The recommended approach involves implementing strict sanitization of all input fields, applying proper HTML escaping before rendering user data, and ensuring that the application enforces Content Security Policy headers to limit script execution. Additionally, organizations should consider implementing web application firewalls, conducting regular security assessments, and applying the vendor-provided patches as soon as they become available. This vulnerability demonstrates the critical importance of input validation and output encoding in web applications, aligning with ATT&CK technique T1566.001 for malicious input and T1071.001 for application layer protocol usage, as attackers can leverage this flaw to establish persistent access to network management systems through the exploitation of stored XSS vulnerabilities.